The degree of pathogenicity within a group or species of microorganisms or viruses as indicated by case fatality rates and/or the ability of the organism to invade the tissues of the host. The pathogenic capacity of an organism is determined by its VIRULENCE FACTORS.
Those components of an organism that determine its capacity to cause disease but are not required for its viability per se. Two classes have been characterized: TOXINS, BIOLOGICAL and surface adhesion molecules that effect the ability of the microorganism to invade and colonize a host. (From Davis et al., Microbiology, 4th ed. p486)
Proteins found in any species of bacterium.
Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Proteins from BACTERIA and FUNGI that are soluble enough to be secreted to target ERYTHROCYTES and insert into the membrane to form beta-barrel pores. Biosynthesis may be regulated by HEMOLYSIN FACTORS.
The functional hereditary units of BACTERIA.
Toxic substances formed in or elaborated by bacteria; they are usually proteins with high molecular weight and antigenicity; some are used as antibiotics and some to skin test for the presence of or susceptibility to certain diseases.
A phenomenon where microorganisms communicate and coordinate their behavior by the accumulation of signaling molecules. A reaction occurs when a substance accumulates to a sufficient concentration. This is most commonly seen in bacteria.
Physicochemical property of fimbriated (FIMBRIAE, BACTERIAL) and non-fimbriated bacteria of attaching to cells, tissue, and nonbiological surfaces. It is a factor in bacterial colonization and pathogenicity.
Cell-surface components or appendages of bacteria that facilitate adhesion (BACTERIAL ADHESION) to other cells or to inanimate surfaces. Most fimbriae (FIMBRIAE, BACTERIAL) of gram-negative bacteria function as adhesins, but in many cases it is a minor subunit protein at the tip of the fimbriae that is the actual adhesin. In gram-positive bacteria, a protein or polysaccharide surface layer serves as the specific adhesin. What is sometimes called polymeric adhesin (BIOFILMS) is distinct from protein adhesin.
Infections with bacteria of the species ESCHERICHIA COLI.
A species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. aeruginosa is a major agent of nosocomial infection.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
A species of gram-positive, coccoid bacteria isolated from skin lesions, blood, inflammatory exudates, and the upper respiratory tract of humans. It is a group A hemolytic Streptococcus that can cause SCARLET FEVER and RHEUMATIC FEVER.
The interactions between a host and a pathogen, usually resulting in disease.
Proteins isolated from the outer membrane of Gram-negative bacteria.
Distinct units in some bacterial, bacteriophage or plasmid GENOMES that are types of MOBILE GENETIC ELEMENTS. Encoded in them are a variety of fitness conferring genes, such as VIRULENCE FACTORS (in "pathogenicity islands or islets"), ANTIBIOTIC RESISTANCE genes, or genes required for SYMBIOSIS (in "symbiosis islands or islets"). They range in size from 10 - 500 kilobases, and their GC CONTENT and CODON usage differ from the rest of the genome. They typically contain an INTEGRASE gene, although in some cases this gene has been deleted resulting in "anchored genomic islands".
Deoxyribonucleic acid that makes up the genetic material of bacteria.
A genetic rearrangement through loss of segments of DNA or RNA, bringing sequences which are normally separated into close proximity. This deletion may be detected using cytogenetic techniques and can also be inferred from the phenotype, indicating a deletion at one specific locus.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Substances elaborated by bacteria that have antigenic activity.
The genetic complement of a BACTERIA as represented in its DNA.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Potentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.
Proteins obtained from ESCHERICHIA COLI.
Diseases of plants.
The etiologic agent of CHOLERA.
A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.
Thin, hairlike appendages, 1 to 20 microns in length and often occurring in large numbers, present on the cells of gram-negative bacteria, particularly Enterobacteriaceae and Neisseria. Unlike flagella, they do not possess motility, but being protein (pilin) in nature, they possess antigenic and hemagglutinating properties. They are of medical importance because some fimbriae mediate the attachment of bacteria to cells via adhesins (ADHESINS, BACTERIAL). Bacterial fimbriae refer to common pili, to be distinguished from the preferred use of "pili", which is confined to sex pili (PILI, SEX).
The etiologic agent of PLAGUE in man, rats, ground squirrels, and other rodents.
Exotoxins produced by certain strains of streptococci, particularly those of group A (STREPTOCOCCUS PYOGENES), that cause HEMOLYSIS.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
A species of the fungus CRYPTOCOCCUS. Its teleomorph is Filobasidiella neoformans.
Mutagenesis where the mutation is caused by the introduction of foreign DNA sequences into a gene or extragenic sequence. This may occur spontaneously in vivo or be experimentally induced in vivo or in vitro. Proviral DNA insertions into or adjacent to a cellular proto-oncogene can interrupt GENETIC TRANSLATION of the coding sequences or interfere with recognition of regulatory elements and cause unregulated expression of the proto-oncogene resulting in tumor formation.
Infections with bacteria of the genus STREPTOCOCCUS.
Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.
An envelope of loose gel surrounding a bacterial cell which is associated with the virulence of pathogenic bacteria. Some capsules have a well-defined border, whereas others form a slime layer that trails off into the medium. Most capsules consist of relatively simple polysaccharides but there are some bacteria whose capsules are made of polypeptides.
Antibiotic pigment produced by Pseudomonas aeruginosa.
Substances that are toxic to cells; they may be involved in immunity or may be contained in venoms. These are distinguished from CYTOSTATIC AGENTS in degree of effect. Some of them are used as CYTOTOXIC ANTIBIOTICS. The mechanism of action of many of these are as ALKYLATING AGENTS or MITOSIS MODULATORS.
Proteins that are structural components of bacterial fimbriae (FIMBRIAE, BACTERIAL) or sex pili (PILI, SEX).
The relationships of groups of organisms as reflected by their genetic makeup.
A serotype of Salmonella enterica that is a frequent agent of Salmonella gastroenteritis in humans. It also causes PARATYPHOID FEVER.
A species of gram-positive, rod-shaped bacteria widely distributed in nature. It has been isolated from sewage, soil, silage, and from feces of healthy animals and man. Infection with this bacterium leads to encephalitis, meningitis, endocarditis, and abortion.
A test used to determine whether or not complementation (compensation in the form of dominance) will occur in a cell with a given mutant phenotype when another mutant genome, encoding the same mutant phenotype, is introduced into that cell.
Toxins produced, especially by bacterial or fungal cells, and released into the culture medium or environment.
Process of determining and distinguishing species of bacteria or viruses based on antigens they share.
One of the FURANS with a carbonyl thereby forming a cyclic lactone. It is an endogenous compound made from gamma-aminobutyrate and is the precursor of gamma-hydroxybutyrate. It is also used as a pharmacological agent and solvent.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
A unicellular budding fungus which is the principal pathogenic species causing CANDIDIASIS (moniliasis).
The dose amount of poisonous or toxic substance or dose of ionizing radiation required to kill 50% of the tested population.
In GRAM NEGATIVE BACTERIA, multiprotein complexes that function to translocate pathogen protein effector molecules across the bacterial cell envelope, often directly into the host. These effectors are involved in producing surface structures for adhesion, bacterial motility, manipulation of host functions, modulation of host defense responses, and other functions involved in facilitating survival of the pathogen. Several of the systems have homologous components functioning similarly in GRAM POSITIVE BACTERIA.
A human and animal pathogen causing mesenteric lymphadenitis, diarrhea, and bacteremia.
Infections with bacteria of the genus PSEUDOMONAS.
In eukaryotes, a genetic unit consisting of a noncontiguous group of genes under the control of a single regulator gene. In bacteria, regulons are global regulatory systems involved in the interplay of pleiotropic regulatory domains and consist of several OPERONS.
Agents that cause agglutination of red blood cells. They include antibodies, blood group antigens, lectins, autoimmune factors, bacterial, viral, or parasitic blood agglutinins, etc.
A species of the genus YERSINIA, isolated from both man and animal. It is a frequent cause of bacterial gastroenteritis in children.
An acute infectious disease caused by YERSINIA PESTIS that affects humans, wild rodents, and their ectoparasites. This condition persists due to its firm entrenchment in sylvatic rodent-flea ecosystems throughout the world. Bubonic plague is the most common form.
In bacteria, a group of metabolically related genes, with a common promoter, whose transcription into a single polycistronic MESSENGER RNA is under the control of an OPERATOR REGION.
In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.
The destruction of ERYTHROCYTES by many different causal agents such as antibodies, bacteria, chemicals, temperature, and changes in tonicity.
Ability of a microbe to survive under given conditions. This can also be related to a colony's ability to replicate.
A species of gram-negative, anaerobic, rod-shaped bacteria originally classified within the BACTEROIDES genus. This bacterium produces a cell-bound, oxygen-sensitive collagenase and is isolated from the human mouth.
Infections with bacteria of the genus STAPHYLOCOCCUS.
Encrustations, formed from microbes (bacteria, algae, fungi, plankton, or protozoa) embedding in extracellular polymers, that adhere to surfaces such as teeth (DENTAL DEPOSITS); PROSTHESES AND IMPLANTS; and catheters. Biofilms are prevented from forming by treating surfaces with DENTIFRICES; DISINFECTANTS; ANTI-INFECTIVE AGENTS; and antifouling agents.
Infections with bacteria of the genus VIBRIO.
Proteins found in any species of fungus.
Substances that reduce the growth or reproduction of BACTERIA.
Enumeration by direct count of viable, isolated bacterial, archaeal, or fungal CELLS or SPORES capable of growth on solid CULTURE MEDIA. The method is used routinely by environmental microbiologists for quantifying organisms in AIR; FOOD; and WATER; by clinicians for measuring patients' microbial load; and in antimicrobial drug testing.
Established cell cultures that have the potential to propagate indefinitely.
A species of gram-negative, aerobic bacteria that is the causative agent of WHOOPING COUGH. Its cells are minute coccobacilli that are surrounded by a slime sheath.
Discrete segments of DNA which can excise and reintegrate to another site in the genome. Most are inactive, i.e., have not been found to exist outside the integrated state. DNA transposable elements include bacterial IS (insertion sequence) elements, Tn elements, the maize controlling elements Ac and Ds, Drosophila P, gypsy, and pogo elements, the human Tigger elements and the Tc and mariner elements which are found throughout the animal kingdom.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
A species of halophilic bacteria in the genus VIBRIO, which lives in warm SEAWATER. It can cause infections in those who eat raw contaminated seafood or have open wounds exposed to seawater.
The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)
Techniques to alter a gene sequence that result in an inactivated gene, or one in which the expression can be inactivated at a chosen time during development to study the loss of function of a gene.
A species of bacteria that causes ANTHRAX in humans and animals.
Inflammatory responses of the epithelium of the URINARY TRACT to microbial invasions. They are often bacterial infections with associated BACTERIURIA and PYURIA.
A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus CAMPYLOBACTER, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus HELICOBACTER. It has been officially transferred to Helicobacter gen. nov. (see Int J Syst Bacteriol 1989 Oct;39(4):297-405).
A bacterium which is one of the etiologic agents of bacillary dysentery (DYSENTERY, BACILLARY) and sometimes of infantile gastroenteritis.
Infections with bacteria of the genus YERSINIA.
Low-molecular-weight compounds produced by microorganisms that aid in the transport and sequestration of ferric iron. (The Encyclopedia of Molecular Biology, 1994)
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
A genus of gram-negative, facultatively anaerobic rod- to coccobacillus-shaped bacteria that occurs in a broad spectrum of habitats.
Infections with bacteria of the species YERSINIA PSEUDOTUBERCULOSIS.
Infection with a fungus of the species CRYPTOCOCCUS NEOFORMANS.
The determination of the pattern of genes expressed at the level of GENETIC TRANSCRIPTION, under specific circumstances or in a specific cell.
Polysaccharides found in bacteria and in capsules thereof.
A verocytotoxin-producing serogroup belonging to the O subfamily of Escherichia coli which has been shown to cause severe food-borne disease. A strain from this serogroup, serotype H7, which produces SHIGA TOXINS, has been linked to human disease outbreaks resulting from contamination of foods by E. coli O157 from bovine origin.
Genomes of temperate BACTERIOPHAGES integrated into the DNA of their bacterial host cell. The prophages can be duplicated for many cell generations until some stimulus induces its activation and virulence.
Strains of ESCHERICHIA COLI that are a subgroup of SHIGA-TOXIGENIC ESCHERICHIA COLI. They cause non-bloody and bloody DIARRHEA; HEMOLYTIC UREMIC SYNDROME; and hemorrhagic COLITIS. An important member of this subgroup is ESCHERICHIA COLI O157-H7.
The natural bactericidal property of BLOOD due to normally occurring antibacterial substances such as beta lysin, leukin, etc. This activity needs to be distinguished from the bactericidal activity contained in a patient's serum as a result of antimicrobial therapy, which is measured by a SERUM BACTERICIDAL TEST.
Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.
Substances that are toxic to the intestinal tract causing vomiting, diarrhea, etc.; most common enterotoxins are produced by bacteria.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
Microscopic threadlike filaments in FUNGI that are filled with a layer of protoplasm. Collectively, the hyphae make up the MYCELIUM.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
A gram-positive organism found in the upper respiratory tract, inflammatory exudates, and various body fluids of normal and/or diseased humans and, rarely, domestic animals.
A set of BACTERIAL ADHESINS and TOXINS, BIOLOGICAL produced by BORDETELLA organisms that determine the pathogenesis of BORDETELLA INFECTIONS, such as WHOOPING COUGH. They include filamentous hemagglutinin; FIMBRIAE PROTEINS; pertactin; PERTUSSIS TOXIN; ADENYLATE CYCLASE TOXIN; dermonecrotic toxin; tracheal cytotoxin; Bordetella LIPOPOLYSACCHARIDES; and tracheal colonization factor.
A species of gram-positive, coccoid bacteria commonly isolated from clinical specimens and the human intestinal tract. Most strains are nonhemolytic.
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
A genus of VIBRIONACEAE, made up of short, slightly curved, motile, gram-negative rods. Various species produce cholera and other gastrointestinal disorders as well as abortion in sheep and cattle.
Infections in animals with bacteria of the genus SALMONELLA.
An acute diarrheal disease endemic in India and Southeast Asia whose causative agent is VIBRIO CHOLERAE. This condition can lead to severe dehydration in a matter of hours unless quickly treated.
An increased liquidity or decreased consistency of FECES, such as running stool. Fecal consistency is related to the ratio of water-holding capacity of insoluble solids to total water, rather than the amount of water present. Diarrhea is not hyperdefecation or increased fecal weight.
A species of gram-negative, fluorescent, phytopathogenic bacteria in the genus PSEUDOMONAS. It is differentiated into approximately 50 pathovars with different plant pathogenicities and host specificities.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that is frequently isolated from clinical specimens. Its most common site of infection is the urinary tract.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that causes vascular wilts on a wide range of plant species. It was formerly named Erwinia chrysanthemi.
Thin, filamentous protein structures, including proteinaceous capsular antigens (fimbrial antigens), that mediate adhesion of E. coli to surfaces and play a role in pathogenesis. They have a high affinity for various epithelial cells.
Diffusible gene products that act on homologous or heterologous molecules of viral or cellular DNA to regulate the expression of proteins.
Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.
The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.
Cells that line the inner and outer surfaces of the body by forming cellular layers (EPITHELIUM) or masses. Epithelial cells lining the SKIN; the MOUTH; the NOSE; and the ANAL CANAL derive from ectoderm; those lining the RESPIRATORY SYSTEM and the DIGESTIVE SYSTEM derive from endoderm; others (CARDIOVASCULAR SYSTEM and LYMPHATIC SYSTEM) derive from mesoderm. Epithelial cells can be classified mainly by cell shape and function into squamous, glandular and transitional epithelial cells.
The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.
A species of STREPTOCOCCUS isolated from pigs. It is a pathogen of swine but rarely occurs in humans.
A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria that utilizes citrate as a sole carbon source. It is pathogenic for humans, causing enteric fevers, gastroenteritis, and bacteremia. Food poisoning is the most common clinical manifestation. Organisms within this genus are separated on the basis of antigenic characteristics, sugar fermentation patterns, and bacteriophage susceptibility.
The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES).
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that may be pathogenic for frogs, fish, and mammals, including man. In humans, cellulitis and diarrhea can result from infection with this organism.
A whiplike motility appendage present on the surface cells. Prokaryote flagella are composed of a protein called FLAGELLIN. Bacteria can have a single flagellum, a tuft at one pole, or multiple flagella covering the entire surface. In eukaryotes, flagella are threadlike protoplasmic extensions used to propel flagellates and sperm. Flagella have the same basic structure as CILIA but are longer in proportion to the cell bearing them and present in much smaller numbers. (From King & Stansfield, A Dictionary of Genetics, 4th ed)
The ability of bacteria to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).
The outermost layer of a cell in most PLANTS; BACTERIA; FUNGI; and ALGAE. The cell wall is usually a rigid structure that lies external to the CELL MEMBRANE, and provides a protective barrier against physical or chemical agents.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Suspensions of attenuated or killed bacteria administered for the prevention or treatment of infectious bacterial disease.
Genotypic differences observed among individuals in a population.
Hydrolases that specifically cleave the peptide bonds found in PROTEINS and PEPTIDES. Examples of sub-subclasses for this group include EXOPEPTIDASES and ENDOPEPTIDASES.
The type species of LEPORIPOXVIRUS causing infectious myxomatosis, a severe generalized disease, in rabbits. Tumors are not always present.
ENDOPEPTIDASES which have a cysteine involved in the catalytic process. This group of enzymes is inactivated by CYSTEINE PROTEINASE INHIBITORS such as CYSTATINS and SULFHYDRYL REAGENTS.
Diseases of birds which are raised as a source of meat or eggs for human consumption and are usually found in barnyards, hatcheries, etc. The concept is differentiated from BIRD DISEASES which is for diseases of birds not considered poultry and usually found in zoos, parks, and the wild.
Immunoglobulins produced in a response to BACTERIAL ANTIGENS.
Process of generating a genetic MUTATION. It may occur spontaneously or be induced by MUTAGENS.
A toxin produced by certain pathogenic strains of ESCHERICHIA COLI such as ESCHERICHIA COLI O157. It shares 50-60% homology with SHIGA TOXIN and SHIGA TOXIN 1.
A toxin produced by SHIGELLA DYSENTERIAE. It is the prototype of class of toxins that inhibit protein synthesis by blocking the interaction of ribosomal RNA; (RNA, RIBOSOMAL) with PEPTIDE ELONGATION FACTORS.
Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
Diseases of freshwater, marine, hatchery or aquarium fish. This term includes diseases of both teleosts (true fish) and elasmobranchs (sharks, rays and skates).
The relationship between an invertebrate and another organism (the host), one of which lives at the expense of the other. Traditionally excluded from definition of parasites are pathogenic BACTERIA; FUNGI; VIRUSES; and PLANTS; though they may live parasitically.
A set of genes descended by duplication and variation from some ancestral gene. Such genes may be clustered together on the same chromosome or dispersed on different chromosomes. Examples of multigene families include those that encode the hemoglobins, immunoglobulins, histocompatibility antigens, actins, tubulins, keratins, collagens, heat shock proteins, salivary glue proteins, chorion proteins, cuticle proteins, yolk proteins, and phaseolins, as well as histones, ribosomal RNA, and transfer RNA genes. The latter three are examples of reiterated genes, where hundreds of identical genes are present in a tandem array. (King & Stanfield, A Dictionary of Genetics, 4th ed)
A genus in the family XANTHOMONADACEAE whose cells produce a yellow pigment (Gr. xanthos - yellow). It is pathogenic to plants.
The etiologic agent of TULAREMIA in man and other warm-blooded animals.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in fungi.
Hybridization of a nucleic acid sample to a very large set of OLIGONUCLEOTIDE PROBES, which have been attached individually in columns and rows to a solid support, to determine a BASE SEQUENCE, or to detect variations in a gene sequence, GENE EXPRESSION, or for GENE MAPPING.
A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.
A protein present in the cell wall of most Staphylococcus aureus strains. The protein selectively binds to the Fc region of human normal and myeloma-derived IMMUNOGLOBULIN G. It elicits antibody activity and may cause hypersensitivity reactions due to histamine release; has also been used as cell surface antigen marker and in the clinical assessment of B lymphocyte function.
The lipopolysaccharide-protein somatic antigens, usually from gram-negative bacteria, important in the serological classification of enteric bacilli. The O-specific chains determine the specificity of the O antigens of a given serotype. O antigens are the immunodominant part of the lipopolysaccharide molecule in the intact bacterial cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria that occurs singly, in pairs, or in short chains. Its organisms are found in fresh water and sewage and are pathogenic to humans, frogs, and fish.
Procedures for identifying types and strains of bacteria. The most frequently employed typing systems are BACTERIOPHAGE TYPING and SEROTYPING as well as bacteriocin typing and biotyping.
The naturally occurring transmission of genetic information between organisms, related or unrelated, circumventing parent-to-offspring transmission. Horizontal gene transfer may occur via a variety of naturally occurring processes such as GENETIC CONJUGATION; GENETIC TRANSDUCTION; and TRANSFECTION. It may result in a change of the recipient organism's genetic composition (TRANSFORMATION, GENETIC).
Infections caused by bacteria that show up as pink (negative) when treated by the gram-staining method.
A sequence of successive nucleotide triplets that are read as CODONS specifying AMINO ACIDS and begin with an INITIATOR CODON and end with a stop codon (CODON, TERMINATOR).
Methods used by pathogenic organisms to evade a host's immune system.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
A species of gram-positive, aerobic bacteria that produces TUBERCULOSIS in humans, other primates, CATTLE; DOGS; and some other animals which have contact with humans. Growth tends to be in serpentine, cordlike masses in which the bacilli show a parallel orientation.
Infections with bacteria of the family BACTEROIDACEAE.
A bacterium which causes mastitis in cattle and occasionally in man.
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
Infection with a fungus of the genus CANDIDA. It is usually a superficial infection of the moist areas of the body and is generally caused by CANDIDA ALBICANS. (Dorland, 27th ed)
A protein which is a subunit of RNA polymerase. It effects initiation of specific RNA chains from DNA.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that causes rotting, particularly of storage tissues, of a wide variety of plants and causes a vascular disease in CARROTS; and POTATO plants.
Insoluble polymers of TYROSINE derivatives found in and causing darkness in skin (SKIN PIGMENTATION), hair, and feathers providing protection against SUNBURN induced by SUNLIGHT. CAROTENES contribute yellow and red coloration.
Inflammation of the KIDNEY involving the renal parenchyma (the NEPHRONS); KIDNEY PELVIS; and KIDNEY CALICES. It is characterized by ABDOMINAL PAIN; FEVER; NAUSEA; VOMITING; and occasionally DIARRHEA.
A genus of gram-negative, aerobic bacteria whose cells are minute coccobacilli. It consists of both parasitic and pathogenic species.
Infections with organisms of the genus HELICOBACTER, particularly, in humans, HELICOBACTER PYLORI. The clinical manifestations are focused in the stomach, usually the gastric mucosa and antrum, and the upper duodenum. This infection plays a major role in the pathogenesis of type B gastritis and peptic ulcer disease.
A species of EDWARDSIELLA distinguished by its hydrogen sulfide production. (From Bergey's Manual of Determinative Bacteriology, 9th ed)
Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.
Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).
Structures within the nucleus of bacterial cells consisting of or containing DNA, which carry genetic information essential to the cell.
A plant species of the family SOLANACEAE, native of South America, widely cultivated for their edible, fleshy, usually red fruit.
A species of bacteria found in the marine environment, sea foods, and the feces of patients with acute enteritis.
Transport proteins that carry specific substances in the blood or across cell membranes.
An ENTEROTOXIN from VIBRIO CHOLERAE. It consists of two major protomers, the heavy (H) or A subunit and the B protomer which consists of 5 light (L) or B subunits. The catalytic A subunit is proteolytically cleaved into fragments A1 and A2. The A1 fragment is a MONO(ADP-RIBOSE) TRANSFERASE. The B protomer binds cholera toxin to intestinal epithelial cells, and facilitates the uptake of the A1 fragment. The A1 catalyzed transfer of ADP-RIBOSE to the alpha subunits of heterotrimeric G PROTEINS activates the production of CYCLIC AMP. Increased levels of cyclic AMP are thought to modulate release of fluid and electrolytes from intestinal crypt cells.
Gel electrophoresis in which the direction of the electric field is changed periodically. This technique is similar to other electrophoretic methods normally used to separate double-stranded DNA molecules ranging in size up to tens of thousands of base-pairs. However, by alternating the electric field direction one is able to separate DNA molecules up to several million base-pairs in length.
Infections with bacteria of the genus LISTERIA.
Enzymes that transfer the ADP-RIBOSE group of NAD or NADP to proteins or other small molecules. Transfer of ADP-ribose to water (i.e., hydrolysis) is catalyzed by the NADASES. The mono(ADP-ribose)transferases transfer a single ADP-ribose. POLY(ADP-RIBOSE) POLYMERASES transfer multiple units of ADP-ribose to protein targets, building POLY ADENOSINE DIPHOSPHATE RIBOSE in linear or branched chains.
An acute infection caused by the spore-forming bacteria BACILLUS ANTHRACIS. It commonly affects hoofed animals such as sheep and goats. Infection in humans often involves the skin (cutaneous anthrax), the lungs (inhalation anthrax), or the gastrointestinal tract. Anthrax is not contagious and can be treated with antibiotics.
The aggregation of ERYTHROCYTES by AGGLUTININS, including antibodies, lectins, and viral proteins (HEMAGGLUTINATION, VIRAL).
An enzyme that catalyzes the conversion of urea and water to carbon dioxide and ammonia. EC
The presence of viable bacteria circulating in the blood. Fever, chills, tachycardia, and tachypnea are common acute manifestations of bacteremia. The majority of cases are seen in already hospitalized patients, most of whom have underlying diseases or procedures which render their bloodstreams susceptible to invasion.
A polysaccharide-producing species of STREPTOCOCCUS isolated from human dental plaque.
Excrement from the INTESTINES, containing unabsorbed solids, waste products, secretions, and BACTERIA of the DIGESTIVE SYSTEM.
Measurable quantity of bacteria in an object, organism, or organism compartment.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
Cyclic esters of acylated BUTYRIC ACID containing four carbons in the ring.
DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
Inoculation of a series of animals or in vitro tissue with an infectious bacterium or virus, as in VIRULENCE studies and the development of vaccines.
A species of imperfect fungi from which the antibiotic fumigatin is obtained. Its spores may cause respiratory infection in birds and mammals.
Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.
A species of gram-negative bacteria, primarily infecting SWINE, but it can also infect humans, DOGS, and HARES.
A species of gram-negative, aerobic bacteria that is pathogenic for plants.
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
Infections with bacteria of the genus SALMONELLA.
Strains of ESCHERICHIA COLI with the ability to produce at least one or more of at least two antigenically distinct, usually bacteriophage-mediated cytotoxins: SHIGA TOXIN 1 and SHIGA TOXIN 2. These bacteria can cause severe disease in humans including bloody DIARRHEA and HEMOLYTIC UREMIC SYNDROME.
Deletion of sequences of nucleic acids from the genetic material of an individual.
A genus of gram-positive, coccoid bacteria whose organisms occur in pairs or chains. No endospores are produced. Many species exist as commensals or parasites on man or animals with some being highly pathogenic. A few species are saprophytes and occur in the natural environment.
The in vitro fusion of GENES by RECOMBINANT DNA techniques to analyze protein behavior or GENE EXPRESSION REGULATION, or to merge protein functions for specific medical or industrial uses.
The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Proteins which maintain the transcriptional quiescence of specific GENES or OPERONS. Classical repressor proteins are DNA-binding proteins that are normally bound to the OPERATOR REGION of an operon, or the ENHANCER SEQUENCES of a gene until a signal occurs that causes their release.
A species of gram-negative, aerobic bacteria that is the causative agent of LEGIONNAIRES' DISEASE. It has been isolated from numerous environmental sites as well as from human lung tissue, respiratory secretions, and blood.

Import of DNA into mammalian nuclei by proteins originating from a plant pathogenic bacterium. (1/5284)

Import of DNA into mammalian nuclei is generally inefficient. Therefore, one of the current challenges in human gene therapy is the development of efficient DNA delivery systems. Here we tested whether bacterial proteins could be used to target DNA to mammalian cells. Agrobacterium tumefaciens, a plant pathogen, efficiently transfers DNA as a nucleoprotein complex to plant cells. Agrobacterium-mediated T-DNA transfer to plant cells is the only known example for interkingdom DNA transfer and is widely used for plant transformation. Agrobacterium virulence proteins VirD2 and VirE2 perform important functions in this process. We reconstituted complexes consisting of the bacterial virulence proteins VirD2, VirE2, and single-stranded DNA (ssDNA) in vitro. These complexes were tested for import into HeLa cell nuclei. Import of ssDNA required both VirD2 and VirE2 proteins. A VirD2 mutant lacking its C-terminal nuclear localization signal was deficient in import of the ssDNA-protein complexes into nuclei. Import of VirD2-ssDNA-VirE2 complexes was fast and efficient, and was shown to depended on importin alpha, Ran, and an energy source. We report here that the bacterium-derived and plant-adapted protein-DNA complex, made in vitro, can be efficiently imported into mammalian nuclei following the classical importin-dependent nuclear import pathway. This demonstrates the potential of our approach to enhance gene transfer to animal cells.  (+info)

Evidence for a structural motif in toxins and interleukin-2 that may be responsible for binding to endothelial cells and initiating vascular leak syndrome. (2/5284)

The dose-limiting toxicity of interleukin-2 (IL-2) and immunotoxin (IT) therapy in humans is vascular leak syndrome (VLS). VLS has a complex etiology involving damage to vascular endothelial cells (ECs), extravasation of fluids and proteins, interstitial edema, and organ failure. IL-2 and ITs prepared with the catalytic A chain of the plant toxin, ricin (RTA), and other toxins, damage human ECs in vitro and in vivo. Damage to ECs may initiate VLS; if this damage could be avoided without losing the efficacy of ITs or IL-2, larger doses could be administered. In this paper, we provide evidence that a three amino acid sequence motif, (x)D(y), in toxins and IL-2 damages ECs. Thus, when peptides from RTA or IL-2 containing this sequence motif are coupled to mouse IgG, they bind to and damage ECs both in vitro and, in the case of RTA, in vivo. In contrast, the same peptides with a deleted or mutated sequence do not. Furthermore, the peptide from RTA attached to mouse IgG can block the binding of intact RTA to ECs in vitro and vice versa. In addition, RTA, a fragment of Pseudomonas exotoxin A (PE38-lys), and fibronectin also block the binding of the mouse IgG-RTA peptide to ECs, suggesting that an (x)D(y) motif is exposed on all three molecules. Our results suggest that deletions or mutations in this sequence or the use of nondamaging blocking peptides may increase the therapeutic index of both IL-2, as well as ITs prepared with a variety of plant or bacterial toxins.  (+info)

Heparin-binding EGF-like growth factor interacts with mouse blastocysts independently of ErbB1: a possible role for heparan sulfate proteoglycans and ErbB4 in blastocyst implantation. (3/5284)

Blastocyst implantation requires molecular and cellular interactions between the uterine luminal epithelium and blastocyst trophectoderm. We have previously shown that heparin-binding EGF-like growth factor (HB-EGF) is induced in the mouse luminal epithelium solely at the site of blastocyst apposition at 16:00 hours on day 4 of pregnancy prior to the attachment reaction (22:00-23:00 hours), and that HB-EGF promotes blastocyst growth, zona-hatching and trophoblast outgrowth. To delineate which EGF receptors participate in blastocyst activation, the toxicity of chimeric toxins composed of HB-EGF or TGF-(&agr;) coupled to Pseudomonas exotoxin (PE) were used as measures of receptor expression. TGF-(&agr;) or HB-EGF binds to EGF-receptor (ErbB1), while HB-EGF, in addition, binds to ErbB4. The results indicate that ErbB1 is inefficient in mediating TGF-(&agr;)-PE or HB-EGF-PE toxicity as follows: (i) TGF-(&agr;)-PE was relatively inferior in killing blastocysts, 100-fold less than HB-EGF-PE, (ii) analysis of blastocysts isolated from cross-bred egfr+/- mice demonstrated that HB-EGF-PE, but not TGF-(&agr;)-PE, killed egfr-/- blastocysts, and (iii) blastocysts that survived TGF-(&agr;)-PE were nevertheless killed by HB-EGF-PE. HB-EGF-PE toxicity was partially mediated by cell surface heparan sulfate proteoglycans (HSPG), since a peptide corresponding to the heparin-binding domain of HB-EGF as well as heparitinase treatment protected the blastocysts from the toxic effects of HB-EGF-PE by about 40%. ErbB4 is a candidate for being an HB-EGF-responsive receptor since RT-PCR analysis demonstrated that day 4 mouse blastocysts express two different erbB4 isoforms and immunostaining with anti-ErbB4 antibodies confirmed that ErbB4 protein is expressed at the apical surface of the trophectoderm cells. It is concluded that (i) HB-EGF interacts with the blastocyst cell surface via high-affinity receptors other than ErbB1, (ii) the HB-EGF interaction with high-affinity blastocysts receptors is regulated by heparan sulfate, and (iii) ErbB4 is a candidate for being a high-affinity receptor for HB-EGF on the surface of implantation-competent blastocysts.  (+info)

Prevention of graft-versus-host disease (GVHD) by elimination of recipient-reactive donor T cells with recombinant toxins that target the interleukin 2 (IL-2) receptor. (4/5284)

Graft-versus-host disease (GVHD), due to the presence of recipient-reactive T cells, limits the usefulness of bone marrow transplantation (BMT) and is a major contributor to patient mortality. To prevent GVHD, murine and human T cells were activated by antigen or mitogens and treated with a genetically engineered form of Pseudomonas exotoxin A (PE) directed against the IL-2 receptor. Treatment with the chimeric toxin eliminated alloreactive cytotoxic T lymphocytes (CTL) as determined by cytotoxicity and mixed lymphocyte culture assays. Precursor frequencies of alloreactive cytotoxic T cells and proliferative T cells were reduced up to 100-fold as shown by limiting dilution assays. Flow cytometric analyses revealed that treatment with the chimeric toxin completely eliminated CD25+ cells from the cultures. Toxin treatment had no significant effect on hematopoietic stem and progenitor cells as determined in vitro by colony-forming assays and in vivo by long-term hematopoietic recovery after 950 rad irradiation. Toxin treatment decreased GVHD in transplanted mice to less than 10% (as compared to 88% in untreated controls). Thus, it is possible to prevent life-threatening GVHD after BMT by using a CD25 receptor-directed toxin to eliminate host-reactive T cells from bone marrow grafts.  (+info)

Suppression of metastasis formation by a recombinant single chain antibody-toxin targeted to full-length and oncogenic variant EGF receptors. (5/5284)

Cytotoxic strategies which are directed to tumor-associated antigens might be most beneficial for cancer patients with minimal tumor load such as in an adjuvant setting after initial therapy. We have recently described a highly potent single chain antibody-toxin, scFv(14E1)-ETA, which consists of the variable domains of the antibody 14E1 genetically fused to a truncated form of Pseudomonas exotoxin A. ScFv(14E1)-ETA specifically recognizes the human epidermal growth factor receptor (EGFR) and the oncogenically activated receptor variant EGFRvIII, which have been implicated in the development of various human malignancies. Here we have investigated the antimetastatic activity of bacterially expressed scFv(14E1)-ETA and its disulfide-stabilized derivative ds-scFv(14E1)-ETA in a novel model for disseminated disease which is based on murine renal carcinoma cells subsequently transfected with the E. coli beta-galactosidase gene, and human full-length or variant EGFR cDNAs. Intravenous injection of these Renca-lacZ/EGFR and Renca-lacZ/EGFRvIII cells in syngenic Balb/c mice led to the formation of pulmonary metastases which were readily detectable upon excision of the lungs and X-gal staining. Systemic treatment of mice with scFv(14E1)-ETA resulted in the complete suppression of Renca-lacZ/EGFRvIII metastasis formation and drastically reduced the number of pulmonary Renca-lacZ/EGFR tumor nodules. The ds-scFv(14E1)-ETA derivative where the antibody variable regions are connected by an artificial disulfide bond displayed improved thermal stability at physiological temperature but due to reduced cytotoxic activity was less potent than the original scFv(14E1)-ETA in metastasis suppression.  (+info)

Endoprotease PACE4 is Ca2+-dependent and temperature-sensitive and can partly rescue the phenotype of a furin-deficient cell strain. (6/5284)

PACE4 is a member of the eukaryotic subtilisin-like endoprotease family. The expression of human PACE4 in RPE.40 cells (furin-null mutants derived from Chinese hamster ovary K1 cells) resulted in the rescue of a number of wild-type characteristics, including sensitivity to Sindbis virus and the ability to process the low-density-lipoprotein receptor-related protein. Expression of PACE4 in these cells failed to restore wild-type sensitivity to Pseudomonas exotoxin A. Co-expression of human PACE4 in these cells with either a secreted form of the human insulin pro-receptor or the precursor form of von Willebrand factor resulted in both proproteins being processed; RPE.40 cells were unable to process either precursor protein in the absence of co-expressed PACE4. Northern analysis demonstrated that untransfected RPE.40 cells express mRNA species for four PACE4 isoforms, suggesting that any endogenous PACE4 proteins produced by these cells are either non-functional or sequestered in a compartment outside of the secretory pathway. In experiments in vitro, PACE4 processed diphtheria toxin and anthrax toxin protective antigen, but not Pseudomonas exotoxin A. The activity of PACE4 in vitro was Ca2+-dependent and, unlike furin, was sensitive to temperature changes between 22 and 37 degrees C. RPE.40 cells stably expressing human PACE4 secreted an endoprotease with the same Ca2+ dependence and temperature sensitivity as that observed in membrane fractions of these cells assayed in vitro. These results, in conjunction with other published work, demonstrate that PACE4 is an endoprotease with more stringent substrate specificity and more limited operating parameters than furin.  (+info)

Extrahepatic synthesis of plasminogen in the human cornea is up-regulated by interleukins-1alpha and -1beta. (7/5284)

The avascular cornea has limited access to plasma proteins, including plasminogen, a protein that is synthesized by the liver and supplied to most tissues via the blood. Recent experiments by others using plasminogen-deficient mice revealed the importance of plasmin, the active form of plasminogen, for the maintenance of the normal cornea and for corneal wound healing [Kao, Kao, Bugge, Kaufman, Kombrinck, Converse, Good and Degan (1998) Invest. Ophthalmol. Vis. Sci. 39, 502-508; Drew, Kaufman, Kombrinck, Danton, Daugherty, Degen and Bugge (1998) Blood 91, 1616-1624]. In the present experiments, plasmin was identified as a major serine proteinase in the human cornea. The major plasminogen and plasmin forms on non-reducing zymograms and Western blots had Mr values of 76x10(3) and 85x10(3), with minor forms of Mr 200x10(3), 135x10(3), 68x10(3) and 45x10(3). Angiostatin-like peptides with Mrs of 48x10(3), 45x10(3) and 38x10(3) were observed which bound to lysine-Sepharose and reacted with anti-plasminogen monoclonal antibodies directed towards kringle domains 1-3 of plasminogen. The cornea contained 1.1+/-0.15 microgram of plasminogen+plasmin/cornea, or 0.54+/-0.05 microgram of plasminogen+plasmin/mg of protein. Cornea conditioned medium contained nine times the amount of plasminogen+plasmin that could be extracted from the cornea. These data suggested that corneal cells, unlike most extrahepatic cells, synthesize plasminogen. The synthesis of plasminogen by the cornea was confirmed by immunoprecipitation of metabolically labelled plasminogen, sequencing of its cDNA obtained by reverse transcriptase-PCR and inhibition of protein synthesis. Interleukins-1alpha and -1beta stimulated corneal plasminogen synthesis 2-3-fold; however, interleukin-6 decreased corneal plasminogen synthesis by approx. 40% at early times after addition of the cytokine. By 24 h of culture, no differences were noted in the presence and absence of interleukin-6. Thus the cornea can synthesize plasminogen and regulate its synthesis in response to its environment, including cytokines induced in the cornea by injury and inflammation. Therefore the cornea can control the amount of plasminogen, the precursor of both plasmin and angiostatin.  (+info)

Molecular characterization of a flagellar export locus of Helicobacter pylori. (8/5284)

Motility of Helicobacter species has been shown to be essential for successful colonization of the host. We have investigated the organization of a flagellar export locus in Helicobacter pylori. A 7-kb fragment of the H. pylori CCUG 17874 genome was cloned and sequenced, revealing an operon comprising an open reading frame of unknown function (ORF03), essential housekeeping genes (ileS and murB), flagellar export genes (fliI and fliQ), and a homolog to a gene implicated in virulence factor transport in other pathogens (virB11). A promoter for this operon, showing similarity to the Escherichia coli sigma70 consensus, was identified by primer extension. Cotranscription of the genes in the operon was demonstrated by reverse transcription-PCR, and transcription of virB11, fliI, fliQ, and murB was detected in human or mouse biopsies obtained from infected hosts. The genetic organization of this locus was conserved in a panel of H. pylori clinical isolates. Engineered fliI and fliQ mutant strains were completely aflagellate and nonmotile, whereas a virB11 mutant still produced flagella. The fliI and fliQ mutant strains produced reduced levels of flagellin and the hook protein FlgE. Production of OMP4, a member of the outer membrane protein family identified in H. pylori 26695, was reduced in both the virB11 mutant and the fliI mutant, suggesting related functions of the virulence factor export protein (VirB11) and the flagellar export component (FliI).  (+info)

to the scientific community. Here, we provide a comprehensive overview of the research that has been conducted over the first 25 years to identify 394 known or putative virulence factor genes present in the genomes of E. coli O157:H7 strains. Finally, an examination of the conservation of these 394 virulence factor genes across additional genomes of E. coli O157:H7 is provided which summarizes the first 25 years and 13 genomes of this human pathogen. Advances in Microbiology, 4, 390-423. Holly A. Reiland, Morrine A. Omolo, Timothy J. Johnson, and David J. Baumler. ...
Msadek, T., Kunst, F., Henner, D., Klier, A., Rapoport, G., Dedonder, R. (1990) Signal transduction pathway controlling synthesis of a class of degradative enzymes in Bacillus subtilis : expression of the regulatory genes and analysis of mutations in degS and degU. J Bacteriol 172: 824-834. ...
Outer membrane vesicles (OMVs) are nanoscale proteoliposomes secreted from the cell envelope of all Gram-negative bacteria. Originally considered as an artifact of the cell wall, OMVs are now recognized as a general secretion system, which serves to improve the fitness of bacteria and facilitate bacterial interactions in polymicrobial communities as well as interactions between the microbe and the host. In general, OMVs are released in increased amounts from pathogenic bacteria and have been found to harbor much of the contents of the parental bacterium. They mainly encompass components of the outer membrane and the periplasm including various virulence factors such as toxins, adhesins, and immunomodulatory molecules. Numerous studies have clearly shown that the delivery of toxins and other virulence factors via OMVs essentially influences their interactions with host cells. Here, we review the OMV-mediated intracellular deployment of toxins and other virulence factors with a special focus on intestinal
PLOS Pathogens publishes Open Access research and commentary that significantly advance the understanding of pathogens and how they interact with host organisms. Get Started ...
Ahmed Ali Al-Tufaili*, Dr. Falah Salim Manhal, Dr. Ahlam Kadhem Naeem. ABSTRACT. Background: The generally accepted hypothesis today is that UPEC involved from nonpathogenic strains by acquiring new virulence factor from accessory DNA horizontal transfer located at the chromosome or plasmid level. Aim of study: investigate the genetic determination of some pathogenicity-associated virulence factors (PAVFs) genes such as fimH, hlyA and iucC genes in UPEC and capability of transferring of them from UPEC to related and non related species such as E.coli JM 109 and P. aeruginosa as well as evaluation of genes transferring effeciency. Method: During the period from May 2014 to November 2014.a total of 290 samples has been collected from patients suffering from Urinary tract infections (170 samples) and burn infections (120 samples) from Alzahraa and Alsadr teaching Hospital as well as private clinics analytical laboratories and Central Health Laboratory in Al-Najaf Al- Ashraf City Results: seventy ...
c-Jun is a member of the early mammalian transcriptional regulators belonging to the AP-1 family, which participates in a wide range of cellular processes such as proliferation, apoptosis, tumorigenesis, and differentiation. Despite its established role in cell survival upon stress, its participation in the stress response induced by bacterial infections has been poorly investigated. To study the potential role of c-Jun in this context we choose the widely studied α-toxin produced by Staphylococcus aureus, a pore-forming toxin that is a critical virulence factor in the pathogenesis of these bacteria. We analyzed the effect of α-toxin treatment in the activation, expression, and protein levels of c-Jun in A549 lung epithelial cells. Furthermore, we explored the role of c-Jun in the cellular fate after exposure to α-toxin. Our results show that staphylococcal α-toxin per se is able to activate c-Jun by inducing phosphorylation of its Serine 73 residue. Silencing of the JNK (c-Jun N-terminal Kinase)
Authors: Jinoh Kim, Ajitha Thanabalasuriar, Tessa Chaworth-Musters, J Chris Fromme, Elizabeth A Frey, Paula I Lario, Pavel Metalnikov, Keyrillos Rizg, Nikhil A Thomas, Sau Fung Lee, Elizabeth L Hartland, Philip R Hardwidge, Tony Pawson, Natalie C Strynadka, B Brett Finlay, Randy Schekman, Samantha Gruenheid
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BioCentrum is a privately-owned biotechnology service and product provider. The company conducts its own research, development and implementation projects in the area of microbiology and protein chemistry. The special interest is focused on bacterial virulence factors as potential therapeutic targets for drug development and on antibacterial peptides exerting an antibiotic activity.
Date privind numarul de infractiuni comise de minori dupa tipul infractiunii, pe raioane; Minori condamnati pe principalele tipuri de pedepse stabilite de instantele ...
Date privind numarul de infractiuni comise de minori dupa tipul infractiunii, pe raioane; Minori condamnati pe principalele tipuri de pedepse stabilite de instantele ...
TY - JOUR. T1 - Discovery of Salmonella virulence factors translocated via outer membrane vesicles to murine macrophages. AU - Yoon, Hyunjin. AU - Ansong, Charles. AU - Adkins, Joshua N.. AU - Heffron, Fred. PY - 2011/6. Y1 - 2011/6. N2 - Salmonella enterica serovar Typhimurium, an intracellular pathogen and leading cause of food-borne illness, encodes a plethora of virulence effectors. Salmonella virulence factors are translocated into host cells and manipulate host cellular activities, providing a more hospitable environment for bacterial proliferation. In this study, we report a new set of virulence factors that is translocated into the host cytoplasm via bacterial outer membrane vesicles (OMV). PagK (or PagK1), PagJ, and STM2585A (or PagK2) are small proteins composed of ~70 amino acids and have high sequence homology to each other (,85% identity). Salmonella lacking all three homologues was attenuated for virulence in a mouse infection model, suggesting at least partial functional ...
TY - JOUR. T1 - Evaluation of Staphylococcus aureus virulence factors using a silkworm model. AU - Miyazaki, Shinya. AU - Matsumoto, Yasuhiko. AU - Sekimizu, Kazuhisa. AU - Kaito, Chikara. PY - 2012/1/1. Y1 - 2012/1/1. N2 - Previous studies have indicated that the silkworm model is useful for identifying virulence genes of Staphylococcus aureus, a human pathogenic bacterium. Here we examined the scope of S. aureus virulence factors that can be evaluated using the silkworm model. Gene-disrupted mutants of the agr locus, arlS gene and saeS gene, which regulate the expression of cell surface adhesins and hemolysins, exhibited attenuated virulence in silkworms. Mutants of the hla gene encoding α-hemolysin, the hlb gene encoding β-hemolysin, and the psmα and psmβ operons encoding cytolysins, however, showed virulence in silkworms indistinguishable from that of the parent strain. Thus, these S. aureus cytolysins are not required for virulence in silkworms. In contrast, the gene-disrupted mutants ...
FIG. 1. Immunoprecipitation studies with anti-VirB6, anti-VirB7, and anti-VirB9 antisera. (A) Isolation of VirB protein complexes from detergent-solubilized membrane extracts of wild-type A348. (B) VirB complexes isolated from PC1000(pSJB610). Lanes: αB6, αB7, and αB9, anti-VirB antisera; PI, preimmune serum; PA, protein A Sepharose (these were all used for precipitation); Sol. Prot., solubilized starting material for the precipitations; MW, molecular weight markers, with sizes in kilodaltons shown at left. Blots were probed with antiserum to the VirB proteins listed at the right. The cross-reactive material in the blot developed with anti-VirB10 antiserum is heavy-chain IgG, but native VirB10 (48 kDa) and VirB10′ (40 kDa) derived from translation from an internal Met were clearly distinguished from this background in the immunoblots. The IgG light chain also was immunoreactive and formed a nonspecific background in blots developed with the anti-VirB6, -VirB8, and -VirB9 antisera. ...
Bacterial pathogens regulate virulence factor expression at both the level of transcription initiation and mRNA processing/turnover. Within Staphylococcus aureus, virulence factor transcript synthesis is regulated by a number of two-component regulatory systems, the DNA binding protein SarA, and the SarA family of homologues. However, little is known about the factors that modulate mRNA stability or influence transcript degradation within the organism. As our entree to characterizing these processes, S. aureus GeneChips were used to simultaneously determine the mRNA half-lives of all transcripts produced during log-phase growth. It was found that the majority of log-phase transcripts (90%) have a short half-life (|5 min), whereas others are more stable, suggesting that cis- and/or trans-acting factors influence S. aureus mRNA stability. In support of this, it was found that two virulence factor transcripts, cna and spa, were stabilized in a sarA-dependent manner. These results were validated by
virB11, one of the 11 genes of the virB operon, is absolutely required for transport of T-DNA from Agrobacterium tumefaciens into plant cells. Previous studies reported that VirB11 is an ATPase with autophosphorylation activity and localizes to the inner membrane even though the protein does not contain the consensus N-terminal export sequence. In this report, we show that VirB11 localizes to the inner membrane even in the absence of other tumor-inducing (Ti) plasmid-encoded proteins. To facilitate the further characterization of VirB11, we purified this protein from the soluble fraction of an Escherichia coli extract by fusing VirB11 to the maltose-binding protein. The maltose-binding protein-VirB11 fusion was able to complement a virB11 deletion mutant of A. tumefaciens for tumor formation and also localized properly to the inner membrane of A. tumefaciens. The 72-kDa protein, purified from E. coli, exhibited no autophosphorylation, ATPase activity, or ATP-binding activity. To study the ...
Mono- and Stereopictres of 5.0 Angstrom coordination sphere of Arsenic atom in PDB 2vs0: Structural Analysis of Homodimeric Staphylococcal Aureus Virulence Factor Esxa
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Given that antibiotics are losing effectiveness faster than replacements are being found, chemist Timothy Wencewicz suggests we try a new approach. Drugs that hobble the production of virulence factors, small molecules that help bacteria to establish an infection in a host, would put much less selective pressure on bacteria and delay the evolution of resistance. In Infectious Diseases he describes recent work on a target virulence factor.
Knowledge of toxins, virulence factors and antibiotic resistance genes is essential for bio-defense applications aimed at identifying functional signatures for characterizing emerging or engineered pathogens. Whereas genetic signatures identify a pathogen, functional signatures identify what a pathogen is capable of. To facilitate rapid identification of sequences and characterization of genes for signature discovery, we have collected all publicly available (as of this writing), organized sequences representing known toxins, virulence factors, and antibiotic resistance genes in one convenient database, which we believe will be of use to the bio-defense research community. MvirDB integrates DNA and protein sequence information from Tox-Prot, SCORPION, the PRINTS virulence factors, VFDB, TVFac, Islander, ARGO and a subset of VIDA. Entries in MvirDB are hyperlinked back to their original sources. A blast tool allows the user to blast against all DNA or protein sequences in MvirDB, and a browser ...
Staphylococcus aureus is recognized worldwide as one of the major agents of dairy cow intra-mammary infections. This microorganism can express a wide spectrum of pathogenic factors used to attach, colonize, invade and infect the host. The present study evaluated 120 isolates from eight different countries that were genotyped by RS-PCR and investigated for 26 different virulence factors to increase the knowledge on the circulating genetic lineages among the cow population with mastitis. New genotypes were observed for South African strains while for all the other countries new variants of existing genotypes were detected. For each country, a specific genotypic pattern was found. Among the virulence factors, fmtB, cna, clfA and leucocidins genes were the most frequent. The sea and sei genes were present in seven out of eight countries; seh showed high frequency in South American countries (Brazil, Colombia, Argentina), while sel was harboured especially in one Mediterranean country (Tunisia). The ...
Staphylococcus aureus is recognized worldwide as one of the major agents of dairy cow intra-mammary infections. This microorganism can express a wide spectrum of pathogenic factors used to attach, colonize, invade and infect the host. The present study evaluated 120 isolates from eight different countries that were genotyped by RS-PCR and investigated for 26 different virulence factors to increase the knowledge on the circulating genetic lineages among the cow population with mastitis. New genotypes were observed for South African strains while for all the other countries new variants of existing genotypes were detected. For each country, a specific genotypic pattern was found. Among the virulence factors, fmtB, cna, clfA and leucocidins genes were the most frequent. The sea and sei genes were present in seven out of eight countries; seh showed high frequency in South American countries (Brazil, Colombia, Argentina), while sel was harboured especially in one Mediterranean country (Tunisia). The ...
Staphylococcus aureus are widespread bacteria that can cause different infectious diseases, including superficial, invasive, and life-threatening infections. Furtheremore, MRSA is prevalent in hospitals and the community and has become a major concern around the world.. Many different virulence factors, such as surface proteins, are involved in the pathogenesis of these bacteria. One of these important proteins is sasX that has many different roles in this process, including biofilm formation, which helps the bacteria in producing micro colonies and adhesion on the surfaces and bacterial resistance against unexpected conditions (11). Regarding recent studies, SasX had an important role in the pathogenesis of the asian population and ST239 colon (8) and based on its importance, even new studiese have focused on the role of SasX protein in immunization and vaccinaton (9). Furthermore, recent studies have shown that the sasX gene is spreading to other colonies and species (8, 12). On the other ...
Chicago-Virulence factors among strains of Escherichia coli thatcause prostatitis are more prevalent than among strains that cause pyelonephritisor cystitis, according to a study by Spanish researchers presented at theannual Interscience Conference on Antimicrobial Agents and Chemotherapyhere.
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Microbial entry into host tissue is a critical first step in causing infection in animals and plants. In plants, it has been assumed that microscopic surface openings, such as stomata, serve as passive ports of bacterial entry during infection. Surprisingly, we found that stomatal closure is part of a plant innate immune response to restrict bacterial invasion. Stomatal guard cells of Arabidopsis perceive bacterial surface molecules, which requires the FLS2 receptor, production of nitric oxide, and the guard-cell-specific OST1 kinase. To circumvent this innate immune response, plant pathogenic bacteria have evolved specific virulence factors to effectively cause stomatal reopening as an important pathogenesis strategy. We provide evidence that supports a model in which stomata, as part of an integral innate immune system, act as a barrier against bacterial infection.
LINK TO PAPER HERE … Hmm … did you catch that? HIGHLY SOPHISTICATED MECHANISMS FOR REGULATING VIRULENCE FACTOR EXPRESSION IN RESPONSE TO ENVIRONMENTAL SIGNALS OR BY REVERSIBLE MUTATIONS. So … just as Eric and Dylan were no doubt affected by their environment which in turn was partly to blame for their behavior, in the same way, B. Pertussis is ALSO affected by its environment in the human body and this environment has a direct effect on VIRULENCE FACTOR EXPRESSION, i.e. whether the bacterium is dangerous to humans or not. This definitely calls for more study. (Note to self: do a full blog research article on this). This is a fascinating topic in light of the info on microbe pleomorphism (must read Wiki article on this topic HERE) and the resulting virulence (or non-virulence) discovered by Antoine Bechamp way back in Pasteurs day. To explain simply the difference between Pasteur and Bechamp, Pasteur taught that microbes - viruses and bacteria - are bad guys and you need to have ...
Importantly, this effector-triggered immunity has been shown to be a powerful means of augmenting the defense response specifically to pathogens but not to harmless commensals, and makes a major contribution to how plants cope with microbial attack and restrict pathogen growth. Our previous work revealed in metazoans an innate immune pathway that specifically responds to virulence factors encoded by virulent bacteria that we referred to as AVI (Boyer et al., 2011, Diabate et al., 2015). The identification of such system with similarities to plant ETI is paradigm-shifting and indicates that animals like plants have evolved sophisticated strategies to gauge the virulent potential of microbes and respond commensurately (Stuart et al., 2013). Using the prototypal RhoGTPase targeting toxin CNF1 we proved that the animal host is able to monitor the activity of virulence factors (Boyer et al., 2011). Our initial work has been extended to SopE a Salmonella virulence factor activating RhoGTPases. SopE ...
The type 3 secretion systems (T3SSs) are virulence mechanisms used by various Gram-negative bacteria to overcome the host immunity. They are often target-cell contact induced and activated. Activation results in targeting of virulence effector substrates into host cells. One class of secreted substrates, translocators, are required for the intracellular targeting of the second class, the virulence effectors, into host target cells. T3SSs are mainly regulated at 2 levels; a shift from environmental to host temperature results in low level induction of the system whereas target cell contact further induces and activates the system. In the Yersinia T3SS, YopN, one of the secreted substrates, is involved in the latter level of activation. Under non-inducing conditions, YopN complexes with TyeA, SycN and YscB and this complex suppresses the T3SS via an unknown mechanism. When the system is induced, the complex is believed to dissociate and YopN is secreted resulting in the activation of the system. ...
Originally, TAL proteins are virulence factors of the plant-pathogenic Xanthomonas spp. that are injected into plant cells via a type III secretion system in order to modulate transcription1. For this purpose, their c-terminal end contains a nuclear localisation signal (NLS) and an acidic activation domain. The central part of the TAL protein contains a number of almost similar repeats that mediate specific binding to target loci in the genome (see figure 10). In 2009, two groups have simultaneously pointed out that each of these repeats specifically binds to one base of the target DNA via two amino acids (aa 12 and 13), named the repeat variable diresidues (RVD)2. Moreover, it has been shown that DNA binding of these proteins is highly modular, i.e. the number bases or sequence of the target DNA can be changed by adjusting the number or order of the repeats in the TAL protein, respectively. It is still unclear, how the sequence of DNA binding modules and TALE activity correlate. The minimal ...
Originally, TAL proteins are virulence factors of the plant-pathogen Xanthomonas spp. that are injected into plant cells via a type III secretion system in order to modulate transcription1. For this purpose, their c-terminal end contains a nuclear localisation signal (NLS) and an acidic activation domain. The central part of the TAL protein contains a number of almost similar repeats that mediate specific binding to target loci in the genome (see figure 10). In 2009, two groups have simultaneously pointed out that each of these repeats specifically binds to one base of the target DNA via two amino acids (aa 12 and 13), named the repeat variable diresidues (RVD) 2. Moreover, it has been shown that DNA binding of these proteins is highly modular, i.e. the number or order of bases in the target DNA can be changed by adjusting the number or order of the repeats in the TAL protein, respectively. It is still unclear, how the sequence of DNA binding modules and TALE activity correlate. The minimal ...
is certainly a well-known colonizer from the individual nose area and epidermis, but a human pathogen that triggers a wide spectral range of diseases also. pass on and elevated virulence of CA-MRSA strains. Nevertheless, the web host- and cell-specificity of PVL and various other leukocidins, and having less adequate versions, fuels the controversy and impairs the correct evaluation of their function in pathophysiology. Presently, the systems of pore-formation as well as the contribution of PVL and various other leukocidins Rabbit polyclonal to ZBED5 to pathophysiology are incompletely grasped. This review summarizes our current knowledge of leukocidin pore-formation, understanding gaps, and features recent findings determining novel host-factors mixed up in toxin-host interface. As a total result, this review furthers stresses the intricacy behind leukocidin cytotoxicity as well as the issues linked in the goal to review and understand these main virulence factors. is certainly a significant ...
Virulence genes of pathogenic bacteria, which code for toxins, adhesins, invasins or other virulence factors, may be located on transmissible genetic elements such as transposons, plasmids or bacteriophages. In addition, such genes may be part of particular regions on the bacterial chromosomes, term …
Supplementary MaterialsAs a service to our authors and readers, this journal provides supporting information supplied by the authors. linkers rather than rigid motifs leading to a boost in activity on the prospective receptor and anti\virulence potency. is an opportunistic Gram\bad pathogen. It provokes different acute and chronic infections especially in immune\jeopardized and hospitalized individuals.1 Alarmingly, the occurrence of multi\resistant and pan\resistant strains renders currently available antibiotics ineffective and leads to an urgent need for novel treatment options.2 employs an arsenal of virulence\associated factors that allow this pathogen to be effective in CeMMEC13 various web host organisms and conditions.3 The discharge of several virulence factors is handled and synchronized by an activity called quorum sensing (QS).4 QS allows bacterias to collectively regulate gene appearance based on their people density. Little diffusible substances (car\inducers) are secreted in the ...
Figure 2. As if microbes were puppeteers and we humans were the puppets, microbes can control what we eat by a number of marked mechanisms. Adapted from Alcock et al 2014.. People who have desires of chocolate have different microbial metabolites in urine from people indifferent to chocolate, despite having the same diet.. Dysphoria, id est, human discomfort until we eat food which improve microbial welfare, may be due to the expression of bacterial virulence genes and perception of pain by the host. This is because the production of toxins is often triggered by a low concentration of nutrients limiting growth. The detection of sugars and other nutrients regulates virulence and growth of various microbes. These directly injure the intestinal epithelium when nutrients are absent. According to this hypothesis, it has been shown that bacterial virulence proteins activate pain receptors. It has been shown that fasting in mice increases the perception of pain by a mechanism of vagal ...
Around 20% of human cancers are caused by pathogens such as bacteria. A common feature of the so-called cancer-causing bacteria is their capacity to colonise the tissue for years and to be able to escape the control of our immune system. This capacity is the result of a long lasting co-evolution of the bacterial virulence factors and of the host weapons to counteract the infection. The pathogen is able to persist for years while the host is able to confine the infection in small niches of our body. These infection niches might persist for over 20-40 years and the bodys cells in these niches acquire different features from neighbouring healthy cells. To understand the infection niche we have deconstructed it into building blocks and reconstructed it in the lab. The building blocks are the different cells and the bacteria. The mortar-like substances that keep the building blocks together are the factors needed for the cells to communicate and sustain each other. By regenerating the complexity ...
Electroporation was used to insert purified bacterial virulence effector proteins directly into living eukaryotic cells. Protein localization was monitored by confocal immunofluorescence microscopy. This method allows for studies on trafficking, function, and protein-protein interactions using active exogenous proteins, avoiding the need for heterologous expression in eukaryotic cells. ...
Biofilm formation is now recognized as a key virulence factor for a wide range of chronic microbial infections. While it has been well known for decades that bacteria and fungi in biofilms become highly tolerant of ...
The process of bacterial pathogenesis involves complex and dynamic responses from both pathogen and host. While the host can mount an array of defense mechanisms to counteract an infection, bacterial pathogens utilize a number of virulence mechanisms to help them in their quest to invade, colonize, and infect. The expression pattern of virulence factors such…
Reprezentanti: vancomicina, teicoplanina. Vancomicina Farmacocinetica: Se absoarbe limitat din intestin si se eliminara prin scaun dupa administrare orala. Dupa administrare i.v (500 mg), nivelul plasmatic este maxim dupa 1-2 ore (6-10 mcg/ml).
come-up, holding and cooling. We hypothesize that slow heating rate during come-up stage, as practiced ... objectives of this study are to understand how different heating rates during come-up stage could affect (1) ... heat-stress-response and virulence genes. Compared to fast heating rate, slow rate caused higher expression of heat .... ...
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The conventional method for lignin quantitation in the pulp industry is the Klason lignin and acid-soluble lignin test, which is standardized according to TAPPI[37] or NREL[38] procedure. The cellulose is first decrystallized and partially depolymerized into oligomers by keeping the sample in 72% sulfuric acid at 30 °C for 1 h. Then, the acid is diluted to 4% by adding water, and the depolymerization is completed by either boiling (100 °C) for 4 h or pressure cooking at 2 bar (124 °C) for 1 h. The acid is washed out and the sample dried. The residue that remains is termed Klason lignin. A part of the lignin, acid-soluble lignin (ASL) dissolves in the acid. ASL is quantified by the intensity of its UV absorption peak at 280 nm. The method is suited for wood lignins, but not equally well for varied lignins from different sources. The carbohydrate composition may be also analyzed from the Klason liquors, although there may be sugar breakdown products (furfural and 5-hydroxymethylfurfural). A ...
Citation. Linz B, Ivanov YV, Preston A, Brinkac L, Parkhill J, Kim M, Harris SR, Goodfield LL, Fry NK, Gorringe AR, Nicholson TL, Register KB, Losada L, Harvill ET. Acquisition and Loss of Virulence-associated Factors During Genome Evolution and Speciation in Three Clades of Bordetella Species.. BMC Genomics. 2016 Sep 30; 17: 767.. External Citation. Abstract. The genus Bordetella consists of nine species that include important respiratory pathogens such as the classical species B. bronchiseptica, B. pertussis and B. parapertussis and six more distantly related and less extensively studied species. Here we analyze sequence diversity and gene content of 128 genome sequences from all nine species with focus on the evolution of virulence-associated factors.. ...
Fernandes, I., et al. Secretome Analysis Identifies Potential Virulence Factors of Diplodia corticola, a Fungal Pathogen Involved in Cork Oak (Quercus suber) Decline. Fungal Biotechnology. (118) 5-6, 516-523. 18/05/2014.. ...
General Information: Isolated from a soil sample from Nepal. Causative agent of plague. Specific virulence factors are encoded within pathogenicity islands (PAIs) that are required for the invasive phenotype associated with Yersinia infections. One key virulence plasmid contained by the three human-specific pathogens is pCD1/pYv, which encodes a type III secretion system for the delivery of virulence proteins that contribute to internalization into the host cell. It is the causative agent of plague (bubonic and pulmonary) a devastating disease which has killed millions worldwide. The organism can be transmitted from rats to humans through the bite of an infected flea or from human-to-human through the air during widespread infection. Yersinia pestis is an extremely pathogenic organism that requires very few numbers in order to cause disease, and is often lethal if left untreated. The organism is enteroinvasive, and can survive and propagate in macrophages prior to spreading systemically ...
General Information: Specific virulence factors are encoded within pathogenicity islands (PAIs) that are required for the invasive phenotype associated with Yersinia infections. One key virulence plasmid contained by the three human-specific pathogens is pCD1/pYv, which encodes a type III secretion system for the delivery of virulence proteins that contribute to internalization into the host cell. This species is a food and waterborn pathogen that causes gastroenteritis (inflammation of the mucous membranes of the stomach and intestine) and is able to proliferate at temperatures as low as 4 degrees C. ...
Listeria monocytogenes is a common bacterium that causes human infections, like miscarriage and septicemia. Listeria uses specific virulence factors to produce proteins that will assist in invasion, replication, and escape. By manipulation of the virulence factors through knockout mutants, this study observed their role and importance in the infection and proliferation life cycle. JEG-3 cells, a human placental line, were infected with wild type Listeria or knockout mutants of individual virulence factors, Internalin A&B, Listeriolysin O, and ActA. Through Colony Forming Unit Assay, it was possible to analyze the number of colonies representing the number of Listeria bacteria after definitive time points. Each virulence factor did play a significant role in the growth and infection of Listeria in the JEG-3 cells as fewer colonies were found in the knockout mutant plates than the wild type. Each virulence factor affected a distinct portion of the invasion, replication, and escape cycle. The omission of a
Bacillus anthracis can be identified on the basis of the detection of virulence factor genes located on two plasmids, pXO1 and pXO2. Thus isolates lacking both pXO1 and pXO2 are indistinguishable from closely related B. cereus group bacteria. We developed a multiplex PCR assay for characterization o …
ABSTRACT: Candida albicans is a classical example of causative agent for opportunistic fungal infection. Normally, it colonizes skin, gastrointestinal tract, genital, and mucosal membranes, but in certain condition it may responsible for diseases. This phenomenon was mainly associated with immunological status of the host. However, there were fndings that showed the possibility of putative virulence factors work on the transition of commensally to pathogenic role of the yeast. In this review, some virulence factors were discussed. Indeed, there were factors that may be considered as putative virulence factors of C. albicans. ...
Metagenomic technologies enable the study of microbial genetic material in human biomedical sample types such as stool, nasal, oral, urogenital, skin and bronchoalveolar lavage samples. In addition, environmental samples such as soil, water, air and biofilms can be also be analyzed. Metagenomic data can not only be used to examine healthy microbiomes and shed light on causes, effects, and future therapies for a variety of diseases, but it can also be useful to help understand the environments microbial biodiversity. QIAGEN provides next-generation sequencing technologies for metagenomics, as well as qPCR assays and arrays for verification of sequencing results and screening for specific bacterial species, virulence factor genes, and antibiotic resistance genes ...
Staphylococcus aureus is a major human pathogen with well-characterized bacteriophage contributions to its virulence potential. Recently, we identified plasmidial and episomal prophages in S. aureus strains using an extra-chromosomal DNA (exDNA) isolation and sequencing approach, uncovering the plasmidial phage ϕBU01, which was found to encode important virulence determinants. Here, we expanded our extra-chromosomal sequencing of S. aureus, selecting 15 diverse clinical isolates with known chromosomal sequences for exDNA isolation and next-generation sequencing. We uncovered the presence of additional episomal prophages in 5 of 15 samples, but did not identify any plasmidial prophages. exDNA isolation was found to enrich for circular prophage elements, and qPCR characterization of the strains revealed that such prophage enrichment is detectable only in exDNA samples and would likely be missed in whole-genome DNA preparations (e.g., detection of episomal prophages did not correlate with higher ...
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Complete Genome Sequences of Eight Helicobacter pylori Strains with Different Virulence Factor Genotypes and Methylation Profiles, Isolated from Patients with Diverse Gastrointestinal Diseases on Okinawa Island, Japan, Determined Using PacBio Single-Molecule Real-Time Technology ...
This material is based upon work supported in part by the Office of Research and Sponsored Projects and the National Science Foundation under Grant No. DUE-0963648 and CREST Grant No. HRD-1242122. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF). ...
Our laboratory studies the roles of sensory transduction in bacterial-host interactions. Genes and operons that encode virulence factors are often subject to coordinate regulation in response to environmental signals, and bacterial virulence factors frequently target host cell signaling pathways. Specific areas of interest include: a) biochemical analysis of signal transduction pathways in pathogenic bacteria, b) genetic organization of bacterial virulence regulons, and c) in vivo and in vitro studies of mechanisms of pathogenesis. We are also investigating mechanisms involved in the induction of cytotoxic T cell responses by Listeria monocytogenes (LM). In the course of these studies, we have developed a new class of live Listeria-based vaccines with activity against heterologous pathogens and tumors. In a third project, we have discovered a new class of retroelements, called diversity generating retroelements, which are capable of generating vast amounts diversity in proteins involved in ...
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Education: BSc and MSc in molecular biology from University of Oslo (UiO).. Areas of interest: ESKAPE pathogens, Antimicrobial resistance, Virulence.. I graduated from the University of Oslo in 2020 with a masters degree in molecular biology, where I focused on microbiology. In my masters I worked with Acinetobacter baumannii in the lab of Prof. Ole Andreas Løchen Økstad at UiO. I am currently a PhD student looking more closely into novel virulence factors in Pseudomonas aeruginosa. ...
Mariotti P, Malito E, Biancucci M, Lo Surdo P, Mishra RP, Nardi-Dei V, Savino S, Nissum M, Spraggon G, Grandi G, Bagnoli F, Bottomley MJ. Structural and functional characterization of the Staphylococcus aureus virulence factor and vaccine candidate FhuD2. Biochem J. 2013 Feb 01; 449(3):683-93 ...
This work provides both in vivo and in vitro evidence that S. aureus can survive inside PMN and that this ability is regulated, at least in part, by the global regulator, sar, which governs the synthesis and secretion of several virulence factors (2). These data extend observations made in vitro with PMN and macrophages in the 1950s and 1960s (11, 12, 13, 14) and support current in vitro studies of S. aureus invasion and survival in epithelial cells, endothelial cells, and osteoblasts (16, 17, 18). Taken together, these data clearly indicate that the pathogenesis of S. aureus infection involves both extracellular and intracellular locales. Moreover, our data suggest that S. aureus, like bona fide intracellular pathogens (26), has the ability to invade and survive inside the very cell that is responsible for its destruction. Our electron microscopy studies and those assessing invasion of epithelial cells (17) suggest a possible mechanism by which this could occur. In both epithelial cells and ...
This work provides both in vivo and in vitro evidence that S. aureus can survive inside PMN and that this ability is regulated, at least in part, by the global regulator, sar, which governs the synthesis and secretion of several virulence factors (2). These data extend observations made in vitro with PMN and macrophages in the 1950s and 1960s (11, 12, 13, 14) and support current in vitro studies of S. aureus invasion and survival in epithelial cells, endothelial cells, and osteoblasts (16, 17, 18). Taken together, these data clearly indicate that the pathogenesis of S. aureus infection involves both extracellular and intracellular locales. Moreover, our data suggest that S. aureus, like bona fide intracellular pathogens (26), has the ability to invade and survive inside the very cell that is responsible for its destruction. Our electron microscopy studies and those assessing invasion of epithelial cells (17) suggest a possible mechanism by which this could occur. In both epithelial cells and ...
Read A hypothesis explaining why so many pathogen virulence proteins are moonlighting proteins, Pathogens and Disease on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
Expertise Antibiotic resistance Escherichia coli Virulence factors Role in StARE The University of Aveiro team will evaluate the efficiency of advanced water treatment processes in the removal of genes conferring resistance to antibiotics that are critically important to humans. We will use culture-dependent and independent approaches and our experiments will include the analysis of field…
A new study from researchers in the Department of Biochemistry has shed light on machinery that causes virulence in a group of pathogenic bacteria including Shigella and Salmonella.. The work from Professor Judy Armitages lab, led by Dr Andreas Diepold, reveals intriguing features of the injectisome, an essential virulence factor that is responsible for the transmission of bacterial proteins into host cells. These proteins allow the bacteria to proliferate without being eliminated by the host immune system.. Published in PLoS Biology with collaborators from the Department of Physics in Oxford and the Biozentrum in Basel, the findings suggest the possibility of a novel target for the development of anti-virulence drugs. (1). Read more (Department of Biochemistry website). ...
Study Flashcards On USMLE 2011 Bacterial Toxins/Virulence Factors at Quickly memorize the terms, phrases and much more. makes it easy to get the grade you want!
Novel thiazolidinedione-hydroxamates as inhibitors of Mycobacterium tuberculosis virulence factor Zmp1(2020). Authors: Veronika Slachtova, Marek Sebela, Eveline Torfs, Lauren Oorts, Davie Cappoen, Karel Berka, Vaclav Bazgier, Lucie Brulikova ...
AB - Type IV pili (Tfp), which are key virulence factors in many bacterial pathogens, define a large group of multipurpose filamentous nanomachines widespread in Bacteria and Archaea. Tfp biogenesis is a complex multistep process, which relies on macromolecular assemblies composed of 15 conserved proteins in model gram-negative species. To improve our limited understanding of the molecular mechanisms of filament assembly, we have used a synthetic biology approach to reconstitute, in a nonnative heterologous host, a minimal machinery capable of building Tfp. Here we show that eight synthetic genes are sufficient to promote filament assembly and that the corresponding proteins form a macromolecular complex at the cytoplasmic membrane, which we have purified and characterized biochemically. Our results contribute to a better mechanistic understanding of the assembly of remarkable dynamic filaments nearly ubiquitous in prokaryotes ...
BioCentrum is a privately-owned biotechnology service and product provider. The company conducts its own research, development and implementation projects in the area of microbiology and protein chemistry. The special interest is focused on bacterial virulence factors as potential therapeutic targets for drug development and on antibacterial peptides exerting an antibiotic activity.
Inflammation mediated by the inflammasome and the cytokine IL-1β are some of the earliest and most important alarms to infection. These pathways are responsive to the virulence factors that pathogens use to subvert immune processes, and thus are typically activated only by microbes with potential to cause severe disease. Among the most serious human infections are those caused by the pathogenic streptococci, in part because these species numerous strategies for immune evasion. Since the virulence factor armament of each pathogen is unique, the role of IL-1β and the pathways leading to its activation varies for each infection. This review summarizes the role of IL-1β during infections caused by streptococcal pathogens, with emphasis on emergent mechanisms and concepts countering paradigms determined for other organisms ...
Staphylococcus aureus is an efficient human colonizer and pathogen. S.aureus ability to colonize and/or cause infections in humans is due to its expression of many virulence factors. These virulence factors aid the bacterium in adhering, invading and evading the host´s immune defences. This study focused on exploring the role of two cell wall anchored proteins: Serine-aspartate containing protein ...
Infection, whether acute, chronic, local, or systemic, is something that all surgeons respect and fear. To counter infection, tissue injury activates an acute-phase response mediated by the liver and promotes coagulation, immunity, and tissue regeneration. However, microorganisms are able to survive and disseminate throughout tissues because of virulence factors that they express. These virulence factors…
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... it is an example of a virulence factor from a fungus. Other virulence factors include factors required for biofilm formation (e ... When placed at random, the transposon may be placed next to a virulence factor or placed in the middle of a virulence factor ... Small molecules being investigated for their ability to inhibit virulence factors and virulence factor expression include ... "What are Virulence Factors?". News-Medical.Net. Retrieved 3 June 2021. Cross, Alan S (2008). "What is a virulence factor?". ...
... is a virulence factor produced by some members of the genus Bordetella. Together with the pertussis ... Carbonetti, Nicholas H (March 2010). "Pertussis toxin and adenylate cyclase toxin: key virulence factors of Bordetella ... toxin it is the most important virulence factor of the causative agent of whooping cough, Bordetella pertussis. Bordetella ...
The CFTR inhibitory factor (Cif) is a protein virulence factor secreted by the Gram-negative bacteria Pseudomonas aeruginosa ... Cif is the first example of an EH serving as a virulence factor. Based on structural comparison, it appears that the enzyme ... conductance regulator inhibitory factor Cif reveals novel active-site features of an epoxide hydrolase virulence factor". J ... a virulence factor secreted by Pseudomonas aeruginosa". Acta Crystallogr. F66 (1): 26-28. doi:10.1107/S1744309109047599. PMC ...
The Yersinia enterocolitica Ail protein is a known virulence factor. Proteins in this family are predicted to consist of eight ... Protein domains, Protein families, Outer membrane proteins, Virulence factors). ... Virulence-related outer membrane proteins, or outer surface proteins (Osp) in some contexts, are expressed in the outer ... Lom is found in the bacterial outer membrane, and is homologous to virulence proteins of two other enterobacterial genera. It ...
Virulence factors are the attributes of microorganisms that enable it to colonise a particular niche in its host, overcome the ... Fives-Taylor PM, Meyer DH, Mintz KP, Brissette C (June 1999). "Virulence factors of Actinobacillus actinomycetemcomitans". ... 2000) have categorised the virulence factors of Aggregatibacter actinomycetemcomitans as follows. Samaranayake notes the ... Removal of plaque retentive factors: Local plaque retentive factors such as mal-positioned teeth, overhanging restorations, ...
Molecular biology of virulence factors of Entamoeba histolytica Molecular biology and molecular genetics of multidrug ... Phagocytosis as a virulence factor. J Exp Med, 158(5), 1511-1521. Garcia‐Rivera, G., ... mainly in the genes and proteins that drive the virulence mechanisms of this human parasite, willing to develop a vaccine and ... and genes involved in Entamoeba histolytica phagocytosis The role of the ESCRT machinery in amoeba phagocytosis and virulence ...
The toxin may be considered a virulence factor, since it is crucial for the virulence of L. monocytogenes. Listeriolysin O is a ... Virulence Factors of Pathogenic Bacteria. "Pathogenicity islands in Listeria: LIPI-1." State Key Laboratory for Molecular ... as well as other virulence factors of L. monocytogenes within LIPI-1, is activated by the protein encoded by prfA gene. prfA is ... as well as listeriolysin O and other virulence factors regulated by PrfA, is only produced when L. monocytogenes is in a host. ...
S. schenckii synthesizes melanin both in vitro and in vivo Melanin production is a virulence factor found in many fungi that ... Hogan LH, Klein BS, Levitz SM (October 1996). "Virulence factors of medically important fungi". Clin. Microbiol. Rev. 9 (4): ...
Several virulence factors of P. penneri can make infections from this invasive pathogen more pronounced, persistent, and harder ... Rózalski A, Kwil I, Torzewska A, Baranowska M, Staczek P (2007). "[Proteus bacilli: features and virulence factors]". Postepy ... Similar to other Proteus species, P. penneri has a cell-bound hemolytic factor, which has been shown to facilitate penetration ...
Zhu, Jie; Wang, Tao; Chen, Liang; Du, Hong (2021). "Virulence Factors in Hypervirulent Klebsiella pneumoniae". Frontiers in ... It is typically due to aspiration and alcoholism may be a risk factor, though it is also commonly implicated in hospital- ... Also, the use of antibiotics can be a factor that increases the risk of nosocomial infection with Klebsiella bacteria. Sepsis ... The genetic traits that lead to this pathotype are included in a large virulence plasmid and potentially on additional ...
... is a virulence factor of the Gram-positive bacteria Streptococcus pneumoniae. It is a pore-forming toxin of 53 kDa ... Nov 27, 1998). "The molecular mechanism of pneumolysin, a virulence factor from Streptococcus pneumoniae". Journal of Molecular ... Rubins, JB; Janoff, EN (January 1998). "Pneumolysin: A multifunctional pneumococcal virulence factor". The Journal of ...
... the Virulence Factor Database (VFDB) of pathogenic bacteria, the Victors database of virulence factors in human and animal ... which may prime the conditions for other factors to introduce, or lose, virulence factors. Single Nucleotide Polymorphisms, or ... "VFDB: Virulence Factors of Bacterial Pathogens". Retrieved 8 November 2019. Sayers, Samantha; Li, Li; Ong, ... E.coli was an example of why this is important, with genes encoding virulence factors in two strains of the species differing ...
Motility is another major virulence factor. Since E. amylovora is not an obligate biotroph, it is able to survive outside the ... "Virulence Factors of Erwinia amylovora: A Review". International Journal of Molecular Sciences. 16 (12): 12836-12854. doi: ... The factors that determine whether or not cankers become active are not well known, but it is thought that cankers found on ... In the long-run, fire blight is a very important factor of economy and society.[citation needed] A relatively small number of ...
... s can also be considered virulence factors; in viruses in which viroporins are not essential, their pathogenicity is ...
January 2013). "Virulence factors of the Mycobacterium tuberculosis complex". Virulence. 4 (1): 3-66. doi:10.4161/viru.22329. ... tuberculosis has many virulence factors, which can be divided across lipid and fatty acid metabolism, cell envelope proteins, ... and an outermost capsule of glucans and secreted proteins for virulence. It constantly remodels these layers to survive in ...
Virulence factors are the weapons possessed by pathogens to cause damage to the host, hence they are molecules or bacterial ... Antivirulence is the concept of blocking virulence factors. In regards to bacteria, the idea is to design agents that block ... The antivirulence strategy needs the knowledge of the pathogenic mechanisms and of the virulence factors that underlie them. ... "Two-for-one bacterial virulence factor revealed". Retrieved 17 January 2016. Cascioferro, S., Totsika, M., & ...
Secretion of the effectors is coordinated with expression of other virulence factors via shared regulatory networks. The ... Büttner D, Bonas U (March 2010). "Regulation and secretion of Xanthomonas virulence factors". FEMS Microbiology Reviews. 34 (2 ... April 2018). "Xanthomonas citri T6SS mediates resistance to Dictyostelium predation and is regulated by an ECF σ factor and ... Many of the effectors are presumably redundant as individual deletions of effector genes does not impair virulence, however ...
... and they form virulence factors and as such regulate the switch from their normal growth in the intestine into virulence. The ... Johnson, Rebecca; Mylona, Elli; Frankel, Gad (2018). "Typhoidal Salmonella: Distinctive virulence factors and pathogenesis". ... It is also known that Salmonella plasmid virulence gene spvB enhances bacterial virulence by inhibiting autophagy. Infection ... "Genome sequencing reveals diversification of virulence factor content and possible host adaptation in distinct subpopulations ...
The expression of these virulence factors depends on the environmental conditions at the time of infection (see "environment ... expression of virulence factors will only take place when a sufficiently large population of bacteria is present, which is ... "Pathogenicity and virulence factors of Pseudomonas syringae". Journal of General Plant Pathology. 79 (5): 285-296. doi:10.1007/ ... and plant resistance genes gives rise to the virulence of bacterial pathogens. Generally, a single avirulence gene (in the ...
... isolates carry a range of virulence factors called type III secretion system (T3SS) effector proteins. ... Ichinose, Yuki; Taguchi, Fumiko; Mukaihara, Takafumi (2013). "Pathogenicity and virulence factors of Pseudomonas syringae". J ... Lindow, Steven E.; Arny, Deane C.; Upper, Christen D. (1 October 1982). "Bacterial Ice Nucleation: A Factor in Frost Injury to ... the bacteria change their pattern of gene expression to form a biofilm and begin expression of virulence-related genes. The ...
"Neutrophil elastase targets virulence factors of enterobacteria". Nature. 417 (6884): 91-94. doi:10.1038/417091a. ISSN 1476- ...
... also acts as a virulence factor. It has an antioxidant action that helps the microbe evade death by reactive ... "Staphylococcus aureus golden pigment impairs neutrophil killing and promotes virulence through its antioxidant activity". J Exp ... "A cholesterol biosynthesis inhibitor blocks Staphylococcus aureus virulence". Science. 319 (5868): 391-94. doi:10.1126/science. ...
Mottram, Jeremy C; Coombs, Graham H; Alexander, James (August 2004). "Cysteine peptidases as virulence factors of Leishmania". ... where they function as virulence factors. The enzyme and potential drug target cruzipain is important for the life cycle of the ...
... phylogeny and putative virulence factors". Microbiology. 144 (4): 829-838. doi:10.1099/00221287-144-4-829. PMID 9579058. ...
... is type of neuraminidase and a virulence factor for many bacteria including Bacteroides fragilis and ... attachment factors) bind preferentially. Gaskell A, Crennell S, Taylor G (November 1995). "The three domains of a bacterial ...
This protein degrades the outer membrane protein A (OmpA) of E. coli as well as the virulence factors of such bacteria as ... Weinrauch Y, Drujan D, Shapiro SD, Weiss J, Zychlinsky A (May 2002). "Neutrophil elastase targets virulence factors of ...
Helicobacter pylori virulence factor CagA (cytotoxin-associated gene A) is a 120-145kDa protein encoded on the 40kb cag ... Yamaoka Y (November 2010). "Mechanisms of disease: Helicobacter pylori virulence factors". Nature Reviews. Gastroenterology & ... Virulence factors, Helicobacter pylori, Infectious causes of cancer). ... This phenotype mimics an effect produced by hepatocyte growth factor which may participate in various aspects of cancer, ...
These pili are virulence factors involved in adhesion, especially important in uropathogenic Escherichia coli. The gene ... Genetics, Escherichia coli, Gene expression, Virulence factors). ...
Lipooligosaccharide is considered one possible virulence factor. Since the recent recognition of M. catarrhalis as an important ... as well as determining factors involved with virulence, e.g. complement resistance. ...
Identified Virulence Factors of UPEC : Adherence, State Key Laboratory for Moleclular Virology and Genetic Engineering, Beijing ... The majority of bacterial pathogens exploit specific adhesion to host cells as their main virulence factor. "A large number of ... This prevalence marks them as key microbial virulence factors in addition to a bacterium's ability to produce toxins and resist ... Adhesins are a type of virulence factor. Adherence is an essential step in bacterial pathogenesis or infection, required for ...
v t e (Bacterial proteins, Whooping cough, Virulence factors, All stub articles, Protein stubs). ... which uses this protein as a virulence factor. Adhesin (disambiguation) Locht, C; Bertin, P; Menozzi, FD; Renauld, G. (1993). " ... The filamentous haemagglutinin adhesin (FHA) is a large, filamentous protein that serves as a dominant attachment factor for ...
Host factors associated with severe or fatal Rocky Mountain spotted fever include advanced age, male sex, African or Caribbean ... "Targeted Knockout of the Rickettsia rickettsii OmpA Surface Antigen Does Not Diminish Virulence in a Mammalian Model System". ...
DnaK is part of the heat shock protein 70 family, and aids in the correct synthesis and activation of certain virulence factors ... Lapaque, N., Moriyon, I., Moreno, E., Gorvel, J.P. "Brucella lipopolysaccharide acts as a virulence factor." Curr. Opin. ... The acidic pH is actually essential for replication of the bacteria by inducing major virulence genes of the virB operon and ... "Brucella abortus cyclic beta-1,2-glucan mutants have reduced virulence in mice and are defective in intracellular replication ...
In essence, they are virulence factors, factors that make the bacteria harmful and infective to the host organism. TAAs are ... All Trimeric Autotransporter Adhesins are crucial virulence factors that cause serious disease in humans. The most-studied and ... YadA bacterial adhesin protein domain Type V secretion system Virulence factor Cell adhesion Outer membrane Gram negative ... Virulence factors, Gram-negative bacteria, Secretion, Membrane proteins). ...
... may refer to: M protein (Streptococcus), a virulence factor of the bacterium Streptococcus pyogenes Viral matrix ...
It functions as a Rho GTPase-activating protein (GAP). YopE acts as both a virulence factor and a protective antigen. In order ... In molecular biology, the protein domain YopE refers to the secretion of virulence factors in Gram-negative bacteria involves ... tumor necrosis factor alpha [TNF-alpha] and gamma interferon [IFN]) and by killing bacteria-associated host cells to promote ...
Among her influential contributions are studies that link pneumococcal virulence factors to specific host receptors, the ...
As a result, there are many strains, which vary in virulence. Resistance to Bremia lactucae in Lactuca serriola is due to Dm ... Testing for the presence of new resistance factors is conducted by screening samples of L. serriola with various isolates of B ... Farrara, B. F.; Ilot, T. W.; Michelmore, R. W. (1987). "Genetic analysis of factors for resistance to downy mildew Bremia ... with avirulence being dominant to virulence. The possible combinations of these Dm genes can provide the plant with resistance ...
Pandey, A; Sonti, RV (June 2010). "Role of the FeoB protein and siderophore in promoting virulence of Xanthomonas oryzae pv. ... a Novel Iron Binding Transcription Factor, in the Plant Pathogen Xanthomonas". PLOS Pathog. 12 (11): e1006019. doi:10.1371/ ... Pandey, SS; Patnana, PK; Lomada, SK; Tomar, A; Chatterjee, S (2016). "Co-regulation of Iron Metabolism and Virulence Associated ... Pandey SS, Chatterjee S. Insights into the cell-cell signaling and iron homeostasis in Xanthomonas virulence and lifestyle. ...
... is a surface-exposed and secreted protein that acts as a major virulence attachment factor, functioning as both a primary ...
"Histatins are the major wound-closure stimulating factors in human saliva as identified in a cell culture assay". FASEB Journal ... Virulence. 7 (5): 512-26. doi:10.1080/21505594.2016.1138201. PMC 5026795. PMID 27078171. Khurshid, Zohaib; Najeeb, Shariq; Mali ...
Thiamin and oxaloacetic acid as growth factors. Proc. Soc. Exp. Biol. Med. 58: 199-201. 1945. Biology of Pityrosporum ovalc. ... and virulence, in her studies and publications. Her thesis work Certain Monilias Parasitic on Man, their Identification by ...
Despite this not being a pathogenic bacterium, it possess some virulence genes (including virulence factor mviN, hemolysin or N ... glycosylation gene cluster) which provide insights into the origins of virulence in their pathogenic relatives, Helicobacter ...
Due to these factors, it is vital to raise awareness of the clinical symptoms of biotoxin poisoning, and to develop effective ... Toxins produced by microorganisms are important virulence determinants responsible for microbial pathogenicity and/or evasion ...
A comparative genomic study found that in opportunistic fungi there are few if any specialised virulence traits consistently ... ISBN 978-1-904455-32-5. Martins N, Ferreira IC, Barros L, Silva S, Henriques M (2014). "Candidiasis: predisposing factors, ...
... a probable virulence factor from Neisseria meningitidis". J. Biol. Chem. 277 (14): 12016-22. doi:10.1074/jbc.M112350200. PMID ...
Depending on the strain of H. somni, not all of the listed virulence factors may be present. Due to the role of H. somni as a ... H. somni has numerous virulence factors including surface proteins, binding to and induction of apoptosis in host endothelial ... Inzana, Thomas J. (2016), Inzana, Thomas J. (ed.), "The Many Facets of Lipooligosaccharide as a Virulence Factor for ... and successful disease can be established because of poor environmental factors and the bacteria's own virulence factors. ...
as Potential Virulence Factors for Soft Tunic Syndrome in Halocynthia roretzi. PLoS ONE, 7(12): e52379. DOI: 10.1371/journal. ... Through metatranscriptomics using RNA-seq technology combined with field-emission microscopy the virulence factors of a ...
... virulence factors) to accomplish a specific job and yet, keeping a safe-distance from the defense arsenal of the targeted cells ... 1). It is expected, that environmental factors around the secretory microbes are responsible for inducing these bacteria to ... Exocytosis Host-pathogen interactions Host-pathogen interface List of bacterial disulfide oxidoreductases Virulence Toyofuku, ... endotoxins and allied virulence molecules. This communication happens in microbial cultures in oceans, inside animals, plants ...
High risk factors for grey leaf spot in corn: Susceptible hybrid Continuous corn Late planting date Minimum tillage systems ... cercosporin increases the virulence of Cercospora fungi. Cercospora zeae-maydis survives only as long as infected corn debris ... High risks for corn grey leaf spot are divided into eight factors, which require specific management strategies. ... Both populations share the same symptoms and virulence, the ability of the fungus to invade the host. Major outbreaks of grey ...
Another factor that affects both phenotypic and behavioural plasticity of D. magna is the salinity of its surroundings. D. ... Little, T. J.; Chadwick, W.; Watt, K. (2008-03-01). "Parasite variation and the evolution of virulence in a Daphnia- ...
Africa CW, Nel J, Stemmet M (July 2014). "Anaerobes and bacterial vaginosis in pregnancy: virulence factors contributing to ... In a select subset of high risk patients, granulocyte colony stimulating factors (G-CSF) can be used to aid immune system ... Kong C, Neoh HM, Nathan S (March 2016). "Targeting Staphylococcus aureus Toxins: A Potential form of Anti-Virulence Therapy". ... July 2006). "2006 update of recommendations for the use of white blood cell growth factors: an evidence-based clinical practice ...
Another important factor is the change of the HA protein to a binding preference for alpha-2,6 sialic acid (the major form ... came to the conclusion that it was most notably the polymerase genes and the HA and NA genes that caused the extreme virulence ...
This has been found to be due to nonuse of melanin, which is a virulence factor in M. grisea.: 184 , "Three mutants of M. ... It is able to establish both resistance to those chemical treatments and virulence to crop resistance by genetic change through ...
... have already been infected for several weeks to determine whether antibody against pertussis toxin or another virulence factor ... Single factors are much less useful. In adults with a cough of less than 8 weeks, vomiting after coughing or a "whoop" is ...
For example, LTA from Enterococcus faecalis is a virulence factor positively correlating to inflammatory damage to teeth during ... Binding to TLR-2 has shown to induce NF-κB expression(a central transcription factor), elevating expression of both pro- and ...
"Plasmid-controlled colonization factor associated with virulence in Esherichia coli enterotoxigenic for humans". Infection and ...
This study was able to support as evidence autolysin's contribution in virulence and potential for vaccine antigen. LytC and ... The activity of this sigma factor peaks at the start of the stationary phase. Autolysins are naturally produced by ... Berry AM, Lock RA, Hansman D, Paton JC (August 1989). "Contribution of autolysin to virulence of Streptococcus pneumoniae". ... and lytF genes together leads to flagellar motility and is controlled by the activity of the chemotaxis sigma factor, σD. ...
A major factor contributing to the appearance of new zoonotic pathogens in human populations is increased contact between ... Zoonoses are of interest because they are often previously unrecognized diseases or have increased virulence in populations ... "Factors that may predict next pandemic". ScienceDaily. University of Sydney. Archived from the original on 19 May 2021. ... The researchers found that "pressure on ecosystems, climate change and economic development are key factors" in doing so. More ...
World Health Organization. Regional Office for the Eastern Mediterranean (‎World Health Organization. Regional Office for the Eastern Mediterranean, 2017)‎ ...
Virulence Factors for Hemolytic Uremic Syndrome, Denmark1 On This Page Materials and Methods Results Discussion Cite This ... Associations between virulence factors of Shiga toxin-producing Escherichia coli and disease in humans. J Clin Microbiol. 1999; ... Virulence factors not associated with increased odds of bloody diarrhea included presence of the stx1 gene (not shown) and ... Virulence Factors for Hemolytic Uremic Syndrome, Denmark. Emerging Infectious Diseases. 2004;10(5):842-847. doi:10.3201/ ...
All the latest science news about virulence factors from ...
Learn about Streptococcus, the Streptococcus pyogenes bacterium, the diseases it causes, and its virulence factors. ... Streptococcus pyogenes virulence factors. When a S. pyogenes infection occurs, the bacteria are able to rapidly grow and avoid ... What is Streptococcus? Streptococcus pyogenes, Diseases it Causes, and its Virulence Factors. 2009-06-25. ...
Identification of new Dickeya dadantii virulence factors secreted by the type 2 secretion system. View ORCID ProfileGuy ... We identified four new Out-secreted proteins: the expansin YoaJ, the putative virulence factor VirK and two proteins of the DUF ... We identified four new Out-secreted proteins: the expansin YoaJ, the putative virulence factor VirK and two proteins of the DUF ... Identification of new Dickeya dadantii virulence factors secreted by the type 2 secretion system ...
One large piece of evidence came when the long-sought co-factor for the primary virulence regulator, PrfA, was discovered to be ... Second, glutathione also functions as a post-translational regulator of the pore-forming virulence factor, Listeriolysin O (LLO ... Here we report that robust virulence gene expression can be recapitulated by growing bacteria in a synthetic medium (iLSM) ... facultative intracellular pathogen Listeria monocytogenes coordinates the expression of numerous essential virulence factors by ...
Genotyping and virulence factors of Listeria monocytogenes in terms of food safety. ... Genotyping and virulence factors of Listeria monocytogenes in terms of food safety ... The present study was designed to assess heterogeneity of virulence factors among strains of Listeria monocytogenes isolated ... The virulence characteristics, presence of Listeria pathogenicity island 1 (LIPI-1) as well as inlA, inlB, inlC and inlJ genes ...
One important emerging virulence factor is Panton-Valentine leucocidin (PVL) as more severe clinical sequelae have been ... This wide spectrum of diseases is often linked to the large number of virulence factors produced by S. aureus; from degradative ... since they have the potential to introduce and propagate virulence factors into healthcare facilities. Other practices may help ... Other virulence elements have been reported to lesser extent (Table 2); one of which is toxic shock syndrome toxin (TSST)-1, ...
Our results clearly show the influence of AA and UA on virulence factors of UPEC strains. However, differences between ... Phylogenetic affiliations of UPECs and virulence-associated gene carriage have been identified. PCR analysis revealed that the ... Our results clearly show the influence of AA and UA on virulence factors of UPEC strains. However, differences between ... Effect of asiatic and ursolic acids on growth and virulence factors of uropathogenic Escherichia coli strains ...
Identification of an insertion sequence located in a region encoding virulence factors of Streptococcus pyogenes. *Mark ... both important virulence factors. The same or similar insertion sequences were found in most S. pyogenes strains, but the ... both important virulence factors. The same or similar insertion sequences were found in most S. pyogenes strains, but the ... Identification of an insertion sequence located in a region encoding virulence factors of Streptococcus pyogenes}}, url = {{ ...
Pathogenicity/Virulence Factors Dictionary. This subdictionary is one of several MiniCOPE Dictionaries within COPE and now ... merges the contents of the previous Virulence Factors Dictionary and the contents of the Dictionary of Modulins. ... This dictionary contains entries directly or indirectly bearing on factors that are major pathogenicity determinants of ...
Virulence factors encoding siderophores (24%), T6SSD (25%) and fimbriae (54%) were detected. Conclusions: Our study highlighted ... 2022). Genomic epidemiology, antimicrobial resistance and virulence factors of Enterobacter cloacae complex causing potential ... Genomic epidemiology, antimicrobial resistance and virulence factors of Enterobacter cloacae complex causing potential ...
Enzymatic desialylation of lung epithelium increases binding of lectin PAIIL, Pseudomonas aeruginosa virulence factor. Warning ... Enzymatic desialylation of lung epithelium increases binding of lectin PAIIL, Pseudomonas aeruginosa virulence factor ...
Vaccinia virus protein C6 is a virulence factor that binds TBK-1 adaptor proteins and inhibits activation of IRF3 and IRF7. ... Interferon Regulatory Factor-3, Interferon Regulatory Factor-7, Interferon-beta, NF-kappa B, Open Reading Frames, ... PRRs activate both NF-κB and IFN regulatory factors (IRFs) to activate the IFN-β promoter induction. Data presented here show ... Thus C6 contributes to VACV virulence and might do so via the inhibition of PRR-induced activation of IRF3 and IRF7. ...
Modulation of virulence factors of Staphylococcus aureus by nanostructured surfaces. Paola San-Martin-Galindo, Emil Rosqvist, ... Modulation of virulence factors of Staphylococcus aureus by nanostructured surfaces. In: Materials and design. 2021 ; Vol. 208. ... Modulation of virulence factors of Staphylococcus aureus by nanostructured surfaces. / San-Martin-Galindo, Paola; Rosqvist, ... Modulation of virulence factors of Staphylococcus aureus by nanostructured surfaces. Materials and design. 2021 Oct;208:109879 ...
Therefore, the objective of this work was to detect several virulence factors genes (fimA, papC, papG III, cnf1, hlyA and aer) ... It is necessary to investigate the virulence-associated factors and the ability of horizontal gene transfer among bacteria for ... a good environment for the horizontal transfer of antimicrobial resistance and virulence-associated factors among extended ... a good environment for the horizontal transfer of antimicrobial resistance and virulence-associated factors among extended ...
Thermal regulation can be achieved at the level of DNA, RNA or protein and although many virulence factors are subject to ... Understanding how virulence factors are regulated by temperature presents a significant challenge, as gene expression and ... to control the production of key virulence factors. ... some recent insights into thermal regulation of virulence in ... protein production are often influenced by complex regulatory networks involving multiple transcription factors in bacteria. ...
Virulence factors. Adhesins have specific regions that attach to cell receptor epitopes in a lock-and-key fashion. Mannose- ... UPEC genes encode several postulated virulence factors (VFs), including adhesins, siderophores, protectins, and toxins, as well ... The development of infection is influenced by bacterial factors and host factors. [7] ... Other important factors are the flushing action of urine flow in the ureter and bladder, the inhibition of attachment of type 1 ...
Clonal Lineages, Antibiotic Resistance and Virulence Factors in Vancomycin-Resistant Enterococci Isolated from Fecal Samples of ... Antibiotic Resistance and Virulence Factors in Vancomycin-Resistant Enterococci Isolated from Fecal Samples of Red Foxes ( ...
Virulence factors. Meningococci have 3 important virulence factors, as follows [19] :. * Polysaccharide capsule - Individuals ... Virulence factors of gram-negative bacteria in sepsis with a focus on Neisseria meningitidis. Contrib Microbiol. 2011. 17:31-47 ... In the plasma, soluble coagulation factors are consumed, and the natural inhibitors of coagulation (eg, the tissue factor ... Risk factors include the following:. * Close contact with a patient with primary invasive disease: Epidemics among new recruits ...
Risk Factors Serotype Shiga Toxin 2 Stx Protein Verocytotoxin Virulence Factor Virulence Factors ... Title : Virulence Factors for Hemolytic Uremic Syndrome, Denmark1 Personal Author(s) : Ethelberg, Steen;Olsen, Katharina E. P.; ... risk factors for bloody diarrhea were the eae and stx2 genes, O groups O157 and O103, and increasing age. Risk factors for HUS ... Age Factors Antibiotics Carrier Proteins Child Child, Preschool Cohort Analysis Denmark Diarrhea Epidemiology Escherichia Coli ...
Associations between virulence factors of Shiga toxin--producing Escherichia coli and disease in humans. J Clin Microbiol 1999; ... Whether an illness progresses to HUS depends on strain virulence and host factors (11). Although most persons with diarrhea- ... Virulence factors for hemolytic uremic syndrome, Denmark. Emerg Infect Dis 2004;10:842--7. ... detect virulence factors such as intimin and enterohemolysin, and can differentiate among the subtypes of Shiga toxins (79--81 ...
... , Journal of Clinical Microbiology, December 2005, ASM Journals, DOI: 10.1128/jcm.43.12. ...
... antibiotic resistance genes and virulence factors. Genetic cluster of the A. baumannii strains is the main factor affected the ... were the most commonly detected virulence factors. A. baumannii strains isolated from the chicken meat samples had the highest ... were isolated from 126 animal meat samples and were genotyped by ERIC-PCR method and by PCR detection of their virulence and ... cnf1 and sfa/focDE virulence factors. These high similarities in the pattern of virulence factors of the A. baumannii strains ...
A quorum sensing regulated small volatile molecule reduces acute virulence and promotes chronic infection phenotypes  ... Browsing by Subject "multiple virulence factor regulator". 0-9. Α. Β. Γ. Δ. Ε. Ζ. Η. Θ. Ι. Κ. Λ. Μ. Ν. Ξ. Ο. Π. Ρ. Σ. Τ. Υ. Φ. ...
Virulence factors of Staphylococcus aureus. Cell wall-associated factors:. It consists of a thick peptidoglycan layer, teichoic ... Obesity- causes, risk factors, , on Hypothyroidism: Types, Causes, Symptoms, Treatment ... Inguinal hernia-types, symptoms, causes, risk , on Inguinal canal-boundaries, ... Mycobacterium leprae: morphology, pathogenesis, lab diagnosis , on Leprosy: Symptoms, Classification, MOT, Risk factors, ...
Bacterial toxins and virulence factors in disease / edited by Joel Moss ... [et al.] Contributor(s): Moss, JoelMaterial type: ...
Colonization and Virulence Factors Diversity of H. pylori Infection and Immune Response Treatment Future Research Cite This ... Two other important virulence factors shared by H. pylori and G. hominis are their spiral shape and the motility of their ... The putative virulence factor of H. pylori that has commanded the most attention during the past few years has been its ... Colonization and Virulence Factors. H. pylori multiplies with great efficiency in the hostile environment within the stomach ...
Breaking the Stereotype: Virulence Factor-Mediated Protection of Host Cells in Bacterial Pathogenesis English version České ... Breaking the Stereotype: Virulence Factor-Mediated Protection of Host Cells in Bacterial Pathogenesis ... Vyšlo v časopise: Breaking the Stereotype: Virulence Factor-Mediated Protection of Host Cells in Bacterial Pathogenesis. PLoS ... The Coevolution of Virulence: Tolerance in Perspective * Involvement of the Cytokine MIF in the Snail Host Immune Response to ...
  • In a multivariate logistic regression model, risk factors for bloody diarrhea were the eae and stx 2 genes, O groups O157 and O103, and increasing age. (
  • Risk factors for HUS were presence of the stx 2 (odds ratio [OR] 18.9) and eae (OR undefined) genes, being a child, and having bloody diarrhea. (
  • This process included full O:H serotyping ( 6 ) and determining the presence of the stx 1 , stx 2 , eae (intimin encoding), and ehxA (enterohemolysin encoding) virulence genes by hybridization to individual DNA polynucleotide probes. (
  • We showed that SvfA and SvfB are required for full virulence of D. dadantii and showed that svf genes are present in a variable number of copies in other Pectobacteriaceae , up to three in D. fanghzongdai . (
  • The virulence characteristics, presence of Listeria pathogenicity island 1 (LIPI-1) as well as inlA, inlB, inlC and inlJ genes of tested strains of L. monocytogenes from foods and food processing plants were comparable with human strains independently of particular serotypes. (
  • IS1562 is located in the mga regulon between the genes coding for the M protein and the C5a peptidase, both important virulence factors. (
  • Therefore, the objective of this work was to detect several virulence factors genes (fimA, papC, papG III, cnf1, hlyA and aer) and to determine the conjugative capacity in a wide collection of extended-spectrum β-lactamases-producing E. coli isolated from different sources (human, food, farms, rivers, and wastewater treatment plants). (
  • Regarding virulence genes, fimA, papC, and aer were distributed throughout all the studied environments, papG III was mostly related to clinical strains and wastewater is a route of dissemination for cnf1 and hlyA. (
  • A. baumannii strains with similar genetic cluster (ERIC-Type) had the same prevalence of antibiotic resistance, antibiotic resistance genes and virulence factors. (
  • In the case of opportunistic fungal pathogens, an understanding of host immune dysfunction is as important as an appreciation of which fungal genes may encode definable attributes of virulence. (
  • Specifically, reconstruction of the genes of the 1918 pandemic virus and studies on their contribution to virulence will be important steps toward understanding the biological capabilities of this lethal virus. (
  • In subtractive genomics approach, the essential, virulence and resistance related proteins were retrieved from RefSeq proteome of F. nucleatum by searching against Database of Essential Genes (DEG), Virulence Factor Database (VFDB) and Antibiotic Resistance Gene-ANNOTation (ARG-ANNOT) tool respectively. (
  • The researchers also observed mRNA expression of virulence factor genes sea, agrA, and sarA, and found that Hinoki cypress essential oil inhibited agrA expression at concentrations greater than 0.2 mg/mL, while sea expression and sarA expression were inhibited at a concentration of 0.3 mg/mL. (
  • Intestinal invasion by serovar Abortusovis was significantly reduced after mutation of invH but was not reduced following curing of the virulence plasmid, suggesting that the Salmonella pathogenicity island 1 influences but the virulence plasmid genes do not influence the ability of serovar Abortusovis to invade the intestinal mucosa in sheep. (
  • Several transcription factors and regulators of iron uptake genes were identified, but the knowledge of signaling pathways is still limited. (
  • A type 2 secretion system (T2SS) named Out is necessary for bacterial virulence. (
  • Breaking the Stereotype: Virulence Factor-Mediated Protection of Host Cells in Bacterial Pathogenesis. (
  • Reduced secretion of YopJ by Yersinia limits in vivo cell death but enhances bacterial virulence. (
  • The fungi that cause invasive disease differ considerably in their inherent pathogenicity, even though few, if any, approach the level of virulence of the best known bacterial and viral pathogens. (
  • As such, these factors may play an important role in bacterial reactivation during LTBI. (
  • STEC strains also frequently harbor the locus of enterocyte effacement (LEE) pathogenicity island, which encodes intimin and a number of other virulence factors responsible for the intestinal attaching and effacing lesions ( 2 ). (
  • Several other factors may be involved in the pathogenic process, among them the enterohemolysin produced by many STEC strains ( 2 ). (
  • The present study was designed to assess heterogeneity of virulence factors among strains of Listeria monocytogenes isolated from the food chain and humans in the Czech Republic. (
  • Considering food safety, all tested food strains should still be considered as pathogenic to humans even though some of these showed reduced virulence on the basis of genotyping results. (
  • There is a need for national and regional MRSA surveillance programmes, especially with the emergence of strains that require no underlying risk factors to cause illness, as well as the propagation of chimeric resistance elements in both HA-MRSA and CA-MRSA. (
  • Our results clearly show the influence of AA and UA on virulence factors of UPEC strains. (
  • A total of 22 A. baumanni strains were isolated from 126 animal meat samples and were genotyped by ERIC-PCR method and by PCR detection of their virulence and antimicrobial resistance determinants. (
  • Genetic cluster of the A. baumannii strains is the main factor affected the similarities in the genotypic and phenotypic properties of the A. baumannii strains. (
  • Heatmap and PCoA analysis confirmed this unique virulence profile associated with MDR-PA strains. (
  • The aim of our present study was to screen P. aeruginosa strains isolated from ocular infections, for their potential to produce various phenotypic virulence factors and correlating them with biofilm formation and their antibiotic susceptibility profile. (
  • The isolates were classified as phylogroups B1 (35%), B2 (33%), A (16%) and D (16%), and 14% of the strains had the eae virulence gene. (
  • That, in spite of the fact that there are no structurally variable strains of MTB, therefore all have a similar virulence capacity. (
  • antibiotic resistance, virulence factors and emerging strains. (
  • Among the three identified L. monocytogenes evolutionary lineages, lineage I strains are overrepresented in epidemic listeriosis outbreaks, but the mechanisms underlying the higher virulence potential of strains of this lineage remain elusive. (
  • Here, we demonstrate that Listeriolysin S (LLS), a virulence factor only present in a subset of lineage I strains, is a bacteriocin highly expressed in the intestine of orally infected mice that alters the host intestinal microbiota and promotes intestinal colonization by L. monocytogenes, as well as deeper organ infection. (
  • To our knowledge, these results therefore identify LLS as the first bacteriocin described in L. monocytogenes and associate modulation of host microbiota by L. monocytogenes epidemic strains to increased virulence. (
  • We showed that two of them, SvfA and SvfB, are necessary for the full virulence of the bacteria. (
  • These findings show that identification of all the proteins secreted by the Dickeya Out system is necessary for a better knowledge of the virulence of these bacteria. (
  • Here we report that robust virulence gene expression can be recapitulated by growing bacteria in a synthetic medium (iLSM) containing GSH or other chemical reducing agents. (
  • It is necessary to investigate the virulence-associated factors and the ability of horizontal gene transfer among bacteria for a better understanding of the pathogenicity and the mechanisms of dissemination of resistant bacteria. (
  • Thermal control of virulence factors in bacteria: a hot topic. (
  • Pathogenic bacteria sense environmental cues, including the local temperature, to control the production of key virulence factors. (
  • Understanding how virulence factors are regulated by temperature presents a significant challenge, as gene expression and protein production are often influenced by complex regulatory networks involving multiple transcription factors in bacteria. (
  • Here we highlight some recent insights into thermal regulation of virulence in pathogenic bacteria. (
  • Environmental signals controlling expression of virulence determinants in bacteria. (
  • The evolutionary pressure to combat host defences made these bacteria smart cell biologists and understanding their virulence factors often reveals new knowledge how eukaryotic cells function. (
  • Flavonoids and polyphenols, commonly known for their antioxidant properties, may also repress the growth of certain pathogenic bacteria and are thought to be beneficial dietary factors in gut homeostasis. (
  • Other dietary factors may be harmful, such as iron which has been shown to increase the proliferation and virulence of gut bacteria. (
  • Identification and characterization of a nonimmunoglobulin factor in human saliva that inhibits Streptococcus mutans glucosyltransferase. (
  • Here we report the discovery of a putative innate defense factor in human saliva that inhibits the glucosyltransferase (GTF) of Streptococcus mutans, a virulence enzyme involved in oral colonization by this pathogen. (
  • We present an analysis of strain and patient factors associated with the development of bloody diarrhea and hemolytic uremic syndrome (HUS) among Shiga toxin-producing Escherichia coli (STEC) patients registered in Denmark in a 6-year period. (
  • IMSEAR at SEARO: Study of virulence factors of uropathogenic Escherichia coli and its antibiotic susceptibility pattern. (
  • Repositorio consejería de sanidad de madrid: Interplay among Resistance Profiles, High-Risk Clones, and Virulence in the Caenorhabditis elegans Pseudomonas aeruginosa Infection Model. (
  • Genomic epidemiology, antimicrobial resistance and virulence factors of Enterobacter cloacae complex causing potential community-onset bloodstream infections in a tertiary care hospital of Nepal. (
  • Consistent with previous data, we documented a clear inverse correlation between antimicrobial resistance and virulence in the C. elegans model. (
  • Virulence factors of Candida albicans . (
  • The high affinity iron uptake system of the opportunistic pathogenic yeast Candida albicans has been shown to be essential for virulence. (
  • The protein kinase Ire1 has a Hac1-independent essential role in iron uptake and virulence of Candida albicans. (
  • These include 2 putative virulence factors belonging to ESAT-6 like family of proteins. (
  • Listeria monocytogenes is a Gram-positive intracellular pathogen that is readily amenable to genetic manipulation and for which there are excellent in vitro and in vivo virulence models. (
  • Upon entry to the host cell cytosol, the facultative intracellular pathogen Listeria monocytogenes coordinates the expression of numerous essential virulence factors by allosteric binding of glutathione (GSH) to the Crp-Fnr family transcriptional regulator, PrfA. (
  • Protocols for analyzing L. pneumophila virulence in the G. mellonella model are demonstrated, describing a new tool to aid the understanding of this complex pathogen. (
  • Cryptococcus neoformans is an opportunistic fungal pathogen whose pathogenic lifestyle is linked to its ability to cope with fluctuating levels of copper (Cu), an essential metal involved in multiple virulence mechanisms, within distinct host niches. (
  • Durable resistance to the blast pathogen, Magnaporthe grisea, can be achieved by deploying a resistance gene that recognizes a virulence factor that is essential for the pathogen to cause disease. (
  • In the case of humans, the host species has also shaped pathogen dynamics and virulence viaa multitude of factors from changes in social organization, group size, and exploitation of varied habitats and their animals and plant resources to agriculture, technology, rapid long-distance travel, medicine and global economic integration - which all continue to shape epidemics and the humanhost populations. (
  • Identification of these factors is therefore highly important towards understanding the molecular basis of host-pathogen interactions 6 , 7 . (
  • the rapid shift of virulence in the pathogen population, genetic uniformitity of mega-cultivars, favorability of environmental conditions, and an overlapping/ continuous crop calendar. (
  • Although these organisms have been considered of low virulence, in vitro and in vivo experimental models have provided additional evidence supporting a role for Ureaplasma species (spp. (
  • We identified four new Out-secreted proteins: the expansin YoaJ, the putative virulence factor VirK and two proteins of the DUF 4879 family, SvfA and SvfB. (
  • One of the major class of virulence factors includes effector proteins that are delivered into the host through a type III protein secretion system (TTSS) to suppress plant immune responses, and also to facilitate disease development [ 4 ]. (
  • This dictionary contains entries directly or indirectly bearing on factors that are major pathogenicity determinants of pathogens. (
  • Our aim was to characterize the virulence determinants of MDR P. aeruginosa causing ocular infections. (
  • Other markers, such as motility or pigment production, were not essential for virulence in the C. elegans model but seemed to be related with the higher values of the statistical normalized data. (
  • Aims: The aim of the following study is to assess the virulence factors of uropathogenic E. coli and antibiotic susceptibility pattern. (
  • Conclusions: Therefore, the knowledge of virulence factors of E. coli and their antibiotic susceptibility pattern will help in better understanding of the organism and in the treatment of UTI. (
  • Thermal regulation can be achieved at the level of DNA, RNA or protein and although many virulence factors are subject to thermal regulation, the exact mechanisms of control are yet to be elucidated in many instances. (
  • H37Ra is a virulence attenuated strain of Mycobacterium tuberculosis widely employed as a model to investigate virulence mechanisms. (
  • This assay could also provide an excellent system for investigating the virulence mechanisms of P. syringae . (
  • The highest virulence of ST235 could be attributed to its exoU+ type III secretion system (TTSS) genotype, which was found to be linked with higher virulence in our C. elegans model. (
  • Dissecting virulence: systematic and functional analyses of a pathogenicity island. (
  • Vaccinia virus protein C6 is a virulence factor. (
  • It consists of a thick peptidoglycan layer, teichoic acid, protein-A, and cell surface adhesins (e.g. clumping factor). (
  • The fungus Cryptococcus neoformans straddles the boundary between 'true' and 'opportunistic' virulence, since it is known as a cause of community-acquired infection, even though most instances of cryptococcosis arise in an immunologically compromised host. (
  • Epidemiological and basic studies have provided evidence that infection with H. pylori carrying specific virulence factors can lead to more severe outcome. (
  • The existing knowledge of the L. pneumophila infection cycle in both hosts is summarized at the molecular level and the factors involved within amoeba and macrophages are compared and discussed in the light of recent findings from the Acanthamoeba castellanii genome analyses suggesting the existence of a primitive immune-like system in amoEBa. (
  • In an earlier study performing infection experiments with human primary macrophages and aerosol-infected mice, we identified clade-specific virulence patterns of clinical isolates of MTBC. (
  • Specific risk factors for mortality include sepsis, urinary tract infection, nutritional oedema and hypokalaemia. (
  • In this work, we attempted to decipher the interplay between resistance profiles, high-risk clones, and virulence, testing a large (n = 140) collection of well-characterized P. aeruginosa isolates from different sources (bloodstream infections, nosocomial outbreaks, cystic fibrosis, and the environment) in a Caenorhabditis elegans infection model. (
  • M. tuberculosis encodes for 5 homologues for the resuscitation promoting factor (Rpf), designated rpfA-E which have been shown to be important for reactivation from dormancy and critical for virulence during TB infection. (
  • These data suggest that cytosolic L. monocytogenes interpret a combination of metabolic and redox cues as a signal to initiate robust virulence gene expression in vivo. (
  • Phylogenetic affiliations of UPECs and virulence-associated gene carriage have been identified. (
  • A model for sRNA-mediated control of gene expression that serves as a framework for understanding the regulation of virulence-related properties of L. pneumophila is provided. (
  • This nasal colonization has been identified as a risk factor for later development of endogenous infections 6 , 7 . (
  • Saliva contains an array of nonimmunoglobulin defense factors which are thought to contribute to the protection of the hard and soft tissue surfaces of the oral cavity by modulating microbial colonization and metabolism. (
  • 5 Furthermore, there are other factors at play, such as virulence and interpretation of functional pathways for expounding multifaceted illnesses. (
  • These core genetic pathways may be surveilled for toxin and virulence factor inhibition so that a decrement in function is interpreted as a microbial attack. (
  • H. pylori causes chronic active gastritis and is a major factor in the pathogenesis of duodenal ulcers and, to a lesser extent, gastric ulcers. (
  • Through years of intense scrutinization of dozens of diverse rickettsial genomes, Dr. Gillespie and colleagues have described a large, dynamic mobilome for Rickettsia species, resulting in the identification of integrative conjugative elements as the vehicles for seeding Rickettsia genomes with many of the factors underlying obligate intracellular biology and pathogenesis. (
  • Proteases is said to contribute to pathogenesis through destruction of connective tissue and degradation of host immunological factors [ 20 ] in patients with keratitis. (
  • Several factors such as WNT5a, WNT3a and, as recently shown, WNT6 are important for the interaction of the innate immune system with the adaptive immune system in the pathogenesis of tuberculosis, but also in other inflammatory and infectious diseases. (
  • Pst DC3000 also produces non-proteinaceous virulence effectors, including coronatine (COR), which are crucial for pathogenesis. (
  • The prevalence of these virulence factors is diverse among H. pylori isolated from different geographic areas and ethnic groups, which may explain the differences in disease incidences. (
  • Sophisticated molecular biological research has revealed many virulence attributes in at least four pathogenic fungi, but the future study of fungal virulence requires investigators to distinguish between molecules that directly interact with the host, molecules that regulate these, and molecules that are always required for fungal growth and survival, independent of the host. (
  • The diversity of pathogenic potency, cellular form and route of invasion between fungal species makes it impossible to draw general conclusions about their molecular virulence attributes. (
  • Perception of the high incidence of fungal diseases, particularly those that threaten life, has led to considerable investment in research into fungal virulence, often based on cutting-edge molecular biological approaches. (
  • But the rapid progress made in identifying molecular virulence factors in several fungal pathogens has also raised some caveats and paradoxes that require resolution. (
  • Fungal hemolysins are potential virulence factors. (
  • The virulence factor of E. coli in genitourinary tract infections. (
  • Pertussis: Although no immunologic correlates of protection have yet been identified for pertussis, IgG antibody levels against four virulence factors (pertussis toxin (PT), fimbriae (FIM), filamentous hemagglutinin (FHA), and pertactin (PRN)) are used to assess immunogenicity following vaccination and disease (Mattoo, et al. (
  • However, a simple correlation between the virulence of the MTBC strain used and the inflammatory potential of such an isolate was not observed. (
  • However, the virulence function of a large number of potential virulence effectors encoded by the Pst DC3000 genome and their mode of action is still unknown. (
  • They act as virulence factors and specific effectors that elicit host resistance. (
  • Virulence factors encoding siderophores (24%), T6SSD (25%) and fimbriae (54%) were detected. (
  • The aim of present study is to characterize the resistance and virulence profile of enterococci isolated from aquaculture excavated ponds and masonry tanks (6 samples) in southern Brazil. (
  • Thus C6 contributes to VACV virulence and might do so via the inhibition of PRR-induced activation of IRF3 and IRF7. (
  • Whereas the inhibition of vascular endothelial growth factor (VEGF) has shown promising results in sporadic colon cancer, the role of VEGF signaling in colitis-associated cancer (CAC) has not been addressed. (
  • This review summarizes the evidences of H. pylori virulence factors in relation with gastroduodenal diseases and discusses the geographic differences and appropriate methods of analyzing these virulence markers. (
  • A pneumococcal pilus influences virulence and host inflammatory responses. (
  • In this review, we provide clinical data‐based analyses of how multiple risk factors (such as sex, race, HLA genotypes, blood groups, vitamin D deficiency, obesity, smoking, and asthma) contribute to the inflammatory overactivation and cyto-kine storm (frequently seen in COVID‐19 patients) with a focus on the IL‐6 pathway. (
  • Deletion of VdTrx1 resulted in higher intracellular ROS levels of V. dahliae mycelium , displayed impaired conidial production , and showed significantly reduced virulence on Gossypium hirsutum, and model plants , Arabidopsis thaliana and Nicotiana benthamiana. (
  • This study determined the presence of virulence factors in the organism and correlates it with the multi-drug resistance (MDR). (
  • The polyribosylribitol phosphate (PRP) capsule of Hib is a major virulence factor for the organism. (
  • Molecular studies of virulence in pathogenic fungi reveal a complex interaction between each fungus species and the human host. (
  • Thus, VEGFR-signaling acts as a direct growth factor for tumor cells in CAC, providing a molecular link between inflammation and the development of colon cancer. (
  • Therefore, selection of appropriate virulence markers and testing methods are important when using them to determine risk of diseases. (
  • His early research resulted in the reclassification of Rickettsia species and the identification of many lineage-specific pathogenicity factors . (
  • A recent study on 'Identification of virulence factors of Theileria parva' has confirmed the existence of a low virulent strain and identified the mechanism that was at the basis of this low virulence, showing some promising new avenues to develop a product that could help in the control of Theileriosis. (
  • We studied a cohort of Danish STEC patients and determined risk factors for HUS and bloody diarrhea among a series of microbiologic and patient-related characteristics. (
  • It is found that the p45 element impacts host cell entry and resistance to sodium, both virulence-related characteristics in Legionella species. (
  • In addition, the presence of this bacterium is now recognized as a risk factor for gastric adenocarcinoma and lymphoma. (
  • However, a recent sequencing study of H37Ra, has disproved several genomic differences earlier reported to be associated with virulence. (
  • This work concludes with a presentation of virulence factors common to two or more pathotypes. (
  • One important factor is the introduction of the human immunodeficiency virus (HIV) into areas and populations already having a high TB incidence [ 5 ], the resulting double infections having a disastrous effect. (
  • In conclusion, the rhizosphere of yellow passion fruit may be beneficial for the enrichment of disease-resistant microbes, such as Trichoderma, which may be an important factor inducing stronger resistance to stem rot. (
  • Les résultats des travaux sur l'ultrafiltration ont montré qu'une membrane de 5 kDa (diamètre du pore de 0.015 µm) permet de récolter tous les composés actifs du surnageant, surtout les composés de virulence (les enzymes) qui jouent un rôle important dans le potentiel entomotoxique des biopesticides. (
  • In pathogenic fungi, polyketide and nonribosomal peptides have been shown to be the potential virulence factors and immunosuppressants 1 - 5 . (
  • We also draw comparisons to the virulence and pathophysiology of SARS and MERS to establish parallels in immune response and discuss the potential for therapeutic approaches that may limit disease progression in patients with higher risk profiles than others. (
  • One large piece of evidence came when the long-sought co-factor for the primary virulence regulator, PrfA, was discovered to be the antioxidant tripeptide, glutathione. (
  • Second, glutathione also functions as a post-translational regulator of the pore-forming virulence factor, Listeriolysin O (LLO), by reversibly binding via an S-glutathionylation reaction and preventing membrane association of the LLO monomers. (
  • Les bouillons fermentés, qui comprennent les composants actifs (cellules, spores viables, cristaux de proteines, enzymes, proteines végétatives insecticides, etc.), sont obtenus par fermentation de Btk en bioréacteur de 15 litres. (