Salmonella enterica: A subgenus of Salmonella containing several medically important serotypes. The habitat for the majority of strains is warm-blooded animals.Salmonella typhimurium: A serotype of Salmonella enterica that is a frequent agent of Salmonella gastroenteritis in humans. It also causes PARATYPHOID FEVER.Salmonella: 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.Salmonella Infections: Infections with bacteria of the genus SALMONELLA.Salmonella Infections, Animal: Infections in animals with bacteria of the genus SALMONELLA.Salmonella enteritidis: A serotype of Salmonella enterica which is an etiologic agent of gastroenteritis in man and other animals.Salmonella typhi: A serotype of SALMONELLA ENTERICA which is the etiologic agent of TYPHOID FEVER.Salmonella Food Poisoning: Poisoning caused by ingestion of food harboring species of SALMONELLA. Conditions of raising, shipping, slaughtering, and marketing of domestic animals contribute to the spread of this bacterium in the food supply.Salmonella paratyphi A: A serotype of SALMONELLA ENTERICA that causes mild PARATYPHOID FEVER in humans.Salmonella Phages: Viruses whose host is Salmonella. A frequently encountered Salmonella phage is BACTERIOPHAGE P22.Bacterial Proteins: Proteins found in any species of bacterium.Typhoid Fever: An acute systemic febrile infection caused by SALMONELLA TYPHI, a serotype of SALMONELLA ENTERICA.Salmonella Vaccines: Vaccines or candidate vaccines used to prevent infection with SALMONELLA. This includes vaccines used to prevent TYPHOID FEVER or PARATYPHOID FEVER; (TYPHOID-PARATYPHOID VACCINES), and vaccines used to prevent nontyphoid salmonellosis.Genomic Islands: 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".Gene Expression Regulation, Bacterial: Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.Bacteriophage Typing: A technique of bacterial typing which differentiates between bacteria or strains of bacteria by their susceptibility to one or more bacteriophages.Serotyping: Process of determining and distinguishing species of bacteria or viruses based on antigens they share.Food Microbiology: The presence of bacteria, viruses, and fungi in food and food products. This term is not restricted to pathogenic organisms: the presence of various non-pathogenic bacteria and fungi in cheeses and wines, for example, is included in this concept.Paratyphoid Fever: A prolonged febrile illness commonly caused by several Paratyphi serotypes of SALMONELLA ENTERICA. It is similar to TYPHOID FEVER but less severe.Virulence: 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.Drug Resistance, Multiple, Bacterial: The ability of bacteria to resist or to become tolerant to several structurally and functionally distinct drugs simultaneously. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).Salmonella paratyphi B: A serotype of SALMONELLA ENTERICA which is an agent of PARATYPHOID FEVER in humans.Poultry Diseases: 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.Electrophoresis, Gel, Pulsed-Field: 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.Salmonella arizonae: Gram-negative rods widely distributed in LIZARDS and SNAKES, and implicated in enteric, bone (BONE DISEASES), and joint infections (JOINT DISEASES) in humans.Genes, Bacterial: The functional hereditary units of BACTERIA.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.Eggs: Animal reproductive bodies, or the contents thereof, used as food. The concept is differentiated from OVUM, the anatomic or physiologic entity.Drug Resistance, Bacterial: 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).Plasmids: 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.Microbial Sensitivity Tests: Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).Typhoid-Paratyphoid Vaccines: Vaccines used to prevent TYPHOID FEVER and/or PARATYPHOID FEVER which are caused by various species of SALMONELLA. Attenuated, subunit, and inactivated forms of the vaccines exist.O Antigens: 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)Chickens: Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.Molecular Sequence Data: 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.Microbial Viability: Ability of a microbe to survive under given conditions. This can also be related to a colony's ability to replicate.Integrons: DNA elements that include the component genes and insertion site for a site-specific recombination system that enables them to capture mobile gene cassettes.Flagellin: A protein with a molecular weight of 40,000 isolated from bacterial flagella. At appropriate pH and salt concentration, three flagellin monomers can spontaneously reaggregate to form structures which appear identical to intact flagella.Mutation: 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.Colony Count, Microbial: 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.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)Poultry: Domesticated birds raised for food. It typically includes CHICKENS; TURKEYS, DUCKS; GEESE; and others.Bacterial Typing Techniques: 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.Vaccines, Attenuated: Live vaccines prepared from microorganisms which have undergone physical adaptation (e.g., by radiation or temperature conditioning) or serial passage in laboratory animal hosts or infected tissue/cell cultures, in order to produce avirulent mutant strains capable of inducing protective immunity.Feces: Excrement from the INTESTINES, containing unabsorbed solids, waste products, secretions, and BACTERIA of the DIGESTIVE SYSTEM.Nalidixic Acid: A synthetic 1,8-naphthyridine antimicrobial agent with a limited bacteriocidal spectrum. It is an inhibitor of the A subunit of bacterial DNA GYRASE.Escherichia coli: 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.Food Contamination: The presence in food of harmful, unpalatable, or otherwise objectionable foreign substances, e.g. chemicals, microorganisms or diluents, before, during, or after processing or storage.Flagella: 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)Ciprofloxacin: A broad-spectrum antimicrobial carboxyfluoroquinoline.Cecum: The blind sac or outpouching area of the LARGE INTESTINE that is below the entrance of the SMALL INTESTINE. It has a worm-like extension, the vermiform APPENDIX.Mice, Inbred BALB COperon: 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.Prophages: 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.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Culture Media: 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.DNA Fingerprinting: A technique for identifying individuals of a species that is based on the uniqueness of their DNA sequence. Uniqueness is determined by identifying which combination of allelic variations occur in the individual at a statistically relevant number of different loci. In forensic studies, RESTRICTION FRAGMENT LENGTH POLYMORPHISM of multiple, highly polymorphic VNTR LOCI or MICROSATELLITE REPEAT loci are analyzed. The number of loci used for the profile depends on the ALLELE FREQUENCY in the population.DNA Transposable Elements: 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.Gene Deletion: 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.Polymerase Chain Reaction: 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.Genome, Bacterial: The genetic complement of a BACTERIA as represented in its DNA.Propylene Glycol: A clear, colorless, viscous organic solvent and diluent used in pharmaceutical preparations.Disease Outbreaks: Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.Conjugation, Genetic: A parasexual process in BACTERIA; ALGAE; FUNGI; and ciliate EUKARYOTA for achieving exchange of chromosome material during fusion of two cells. In bacteria, this is a uni-directional transfer of genetic material; in protozoa it is a bi-directional exchange. In algae and fungi, it is a form of sexual reproduction, with the union of male and female gametes.Mutagenesis, Insertional: 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.Lettuce: Any of the various plants of the genus Lactuca, especially L. sativa, cultivated for its edible leaves. (From American Heritage Dictionary, 2d ed)Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Macrophages: 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.)Antibodies, Bacterial: Immunoglobulins produced in a response to BACTERIAL ANTIGENS.Salmonella paratyphi C: A serotype of SALMONELLA ENTERICA which is an agent of PARATYPHOID FEVER in Asia, Africa, and southern Europe.Swine Diseases: Diseases of domestic swine and of the wild boar of the genus Sus.Fimbriae, Bacterial: 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).Escherichia coli Proteins: Proteins obtained from ESCHERICHIA COLI.DNA Gyrase: A bacterial DNA topoisomerase II that catalyzes ATP-dependent breakage of both strands of DNA, passage of the unbroken strands through the breaks, and rejoining of the broken strands. Gyrase binds to DNA as a heterotetramer consisting of two A and two B subunits. In the presence of ATP, gyrase is able to convert the relaxed circular DNA duplex into a superhelix. In the absence of ATP, supercoiled DNA is relaxed by DNA gyrase.Fimbriae Proteins: Proteins that are structural components of bacterial fimbriae (FIMBRIAE, BACTERIAL) or sex pili (PILI, SEX).Antigens, Bacterial: Substances elaborated by bacteria that have antigenic activity.Cattle Diseases: Diseases of domestic cattle of the genus Bos. It includes diseases of cows, yaks, and zebus.Molecular Typing: Using MOLECULAR BIOLOGY techniques, such as DNA SEQUENCE ANALYSIS; PULSED-FIELD GEL ELECTROPHORESIS; and DNA FINGERPRINTING, to identify, classify, and compare organisms and their subtypes.Polysaccharides, Bacterial: Polysaccharides found in bacteria and in capsules thereof.Swine: 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).Bacterial Shedding: The expelling of bacteria from the body. Important routes include the respiratory tract, genital tract, and intestinal tract.Chromosomes, Bacterial: Structures within the nucleus of bacterial cells consisting of or containing DNA, which carry genetic information essential to the cell.CobamidesRegulon: 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.Genetic Complementation Test: 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.Bacterial Adhesion: 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.Food Handling: Any aspect of the operations in the preparation, processing, transport, storage, packaging, wrapping, exposure for sale, service, or delivery of food.Bacterial Load: Measurable quantity of bacteria in an object, organism, or organism compartment.Meat: The edible portions of any animal used for food including domestic mammals (the major ones being cattle, swine, and sheep) along with poultry, fish, shellfish, and game.Poultry Products: Food products manufactured from poultry.Bacterial Vaccines: Suspensions of attenuated or killed bacteria administered for the prevention or treatment of infectious bacterial disease.Anti-Infective Agents: Substances that prevent infectious agents or organisms from spreading or kill infectious agents in order to prevent the spread of infection.Gastroenteritis: INFLAMMATION of any segment of the GASTROINTESTINAL TRACT from ESOPHAGUS to RECTUM. Causes of gastroenteritis are many including genetic, infection, HYPERSENSITIVITY, drug effects, and CANCER.Drug Resistance, Microbial: The ability of microorganisms, especially 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).RNA, Bacterial: Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.beta-Lactamases: Enzymes found in many bacteria which catalyze the hydrolysis of the amide bond in the beta-lactam ring. Well known antibiotics destroyed by these enzymes are penicillins and cephalosporins.Amino Acid Sequence: 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.Tetrathionic Acid: A sulfuric acid dimer, formed by disulfide linkage. This compound has been used to prolong coagulation time and as an antidote in cyanide poisoning.Enterocolitis: Inflammation of the MUCOSA of both the SMALL INTESTINE and the LARGE INTESTINE. Etiology includes ISCHEMIA, infections, allergic, and immune responses.Phosphate Acetyltransferase: An enzyme that catalyzes the synthesis of acetylphosphate from acetyl-CoA and inorganic phosphate. Acetylphosphate serves as a high-energy phosphate compound. EC 2.3.1.8.Lipopolysaccharides: Lipid-containing polysaccharides which are endotoxins and important group-specific antigens. They are often derived from the cell wall of gram-negative bacteria and induce immunoglobulin secretion. The lipopolysaccharide molecule consists of three parts: LIPID A, core polysaccharide, and O-specific chains (O ANTIGENS). When derived from Escherichia coli, lipopolysaccharides serve as polyclonal B-cell mitogens commonly used in laboratory immunology. (From Dorland, 28th ed)Ethanolamine: A viscous, hygroscopic amino alcohol with an ammoniacal odor. It is widely distributed in biological tissue and is a component of lecithin. It is used as a surfactant, fluorimetric reagent, and to remove CO2 and H2S from natural gas and other gases.Coriandrum: A plant genus of the family APIACEAE. The leaves are the source of cilantro and the seeds are the source of coriander, both of which are used in SPICES.Ceftriaxone: A broad-spectrum cephalosporin antibiotic with a very long half-life and high penetrability to meninges, eyes and inner ears.Intestines: The section of the alimentary canal from the STOMACH to the ANAL CANAL. It includes the LARGE INTESTINE and SMALL INTESTINE.Thiamine: 3-((4-Amino-2-methyl-5-pyrimidinyl)methyl)-5-(2- hydroxyethyl)-4-methylthiazolium chloride.TartratesEnteritis: Inflammation of any segment of the SMALL INTESTINE.Peyer's Patches: Lymphoid tissue on the mucosa of the small intestine.Thiamphenicol: A methylsulfonyl analog of CHLORAMPHENICOL. It is an antibiotic and immunosuppressive agent.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Enterobacteriaceae: A family of gram-negative, facultatively anaerobic, rod-shaped bacteria that do not form endospores. Its organisms are distributed worldwide with some being saprophytes and others being plant and animal parasites. Many species are of considerable economic importance due to their pathogenic effects on agriculture and livestock.Cephalosporin Resistance: Non-susceptibility of an organism to the action of the cephalosporins.Sigma Factor: A protein which is a subunit of RNA polymerase. It effects initiation of specific RNA chains from DNA.Lipid A: Lipid A is the biologically active component of lipopolysaccharides. It shows strong endotoxic activity and exhibits immunogenic properties.Ribotyping: RESTRICTION FRAGMENT LENGTH POLYMORPHISM analysis of rRNA genes that is used for differentiating between species or strains.Molecular Epidemiology: The application of molecular biology to the answering of epidemiological questions. The examination of patterns of changes in DNA to implicate particular carcinogens and the use of molecular markers to predict which individuals are at highest risk for a disease are common examples.Site-Specific DNA-Methyltransferase (Adenine-Specific): An enzyme responsible for producing a species-characteristic methylation pattern on adenine residues in a specific short base sequence in the host cell DNA. The enzyme catalyzes the methylation of DNA adenine in the presence of S-adenosyl-L-methionine to form DNA containing 6-methylaminopurine and S-adenosyl-L-homocysteine. EC 2.1.1.72.Drug Resistance, Multiple: Simultaneous resistance to several structurally and functionally distinct drugs.Host-Pathogen Interactions: The interactions between a host and a pathogen, usually resulting in disease.Environmental Microbiology: The study of microorganisms living in a variety of environments (air, soil, water, etc.) and their pathogenic relationship to other organisms including man.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Bacteriological Techniques: Techniques used in studying bacteria.Animals, Domestic: Animals which have become adapted through breeding in captivity to a life intimately associated with humans. They include animals domesticated by humans to live and breed in a tame condition on farms or ranches for economic reasons, including LIVESTOCK (specifically CATTLE; SHEEP; HORSES; etc.), POULTRY; and those raised or kept for pleasure and companionship, e.g., PETS; or specifically DOGS; CATS; etc.Quinolones: A group of derivatives of naphthyridine carboxylic acid, quinoline carboxylic acid, or NALIDIXIC ACID.Vaccines, Synthetic: Small synthetic peptides that mimic surface antigens of pathogens and are immunogenic, or vaccines manufactured with the aid of recombinant DNA techniques. The latter vaccines may also be whole viruses whose nucleic acids have been modified.Polymyxin B: A mixture of polymyxins B1 and B2, obtained from Bacillus polymyxa strains. They are basic polypeptides of about eight amino acids and have cationic detergent action on cell membranes. Polymyxin B is used for infections with gram-negative organisms, but may be neurotoxic and nephrotoxic.Spleen: An encapsulated lymphatic organ through which venous blood filters.Bacterial Outer Membrane Proteins: Proteins isolated from the outer membrane of Gram-negative bacteria.Species Specificity: 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.Bacteriophage P22: A species of temperate bacteriophage in the genus P22-like viruses, family PODOVIRIDAE, that infects SALMONELLA species. The genome consists of double-stranded DNA, terminally redundant, and circularly permuted.Disinfectants: Substances used on inanimate objects that destroy harmful microorganisms or inhibit their activity. Disinfectants are classed as complete, destroying SPORES as well as vegetative forms of microorganisms, or incomplete, destroying only vegetative forms of the organisms. They are distinguished from ANTISEPTICS, which are local anti-infective agents used on humans and other animals. (From Hawley's Condensed Chemical Dictionary, 11th ed)Bacterial Secretion Systems: 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.Shigella: A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria that ferments sugar without gas production. Its organisms are intestinal pathogens of man and other primates and cause bacillary dysentery (DYSENTERY, BACILLARY).Cluster Analysis: A set of statistical methods used to group variables or observations into strongly inter-related subgroups. In epidemiology, it may be used to analyze a closely grouped series of events or cases of disease or other health-related phenomenon with well-defined distribution patterns in relation to time or place or both.Fluoroquinolones: A group of QUINOLONES with at least one fluorine atom and a piperazinyl group.Meat Products: Articles of food which are derived by a process of manufacture from any portion of carcasses of any animal used for food (e.g., head cheese, sausage, scrapple).Gene Transfer, Horizontal: 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).Antibiosis: A natural association between organisms that is detrimental to at least one of them. This often refers to the production of chemicals by one microorganism that is harmful to another.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Artificial Gene Fusion: 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.Acids: Chemical compounds which yield hydrogen ions or protons when dissolved in water, whose hydrogen can be replaced by metals or basic radicals, or which react with bases to form salts and water (neutralization). An extension of the term includes substances dissolved in media other than water. (Grant & Hackh's Chemical Dictionary, 5th ed)Abattoirs: Places where animals are slaughtered and dressed for market.Cation Transport Proteins: Membrane proteins whose primary function is to facilitate the transport of positively charged molecules (cations) across a biological membrane.Biofilms: 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.Escherichia coli O157: 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.Administration, Oral: The giving of drugs, chemicals, or other substances by mouth.Foodborne Diseases: Acute illnesses, usually affecting the GASTROINTESTINAL TRACT, brought on by consuming contaminated food or beverages. Most of these diseases are infectious, caused by a variety of bacteria, viruses, or parasites that can be foodborne. Sometimes the diseases are caused by harmful toxins from the microbes or other chemicals present in the food. Especially in the latter case, the condition is often called food poisoning.Intestinal Mucosa: Lining of the INTESTINES, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. In the SMALL INTESTINE, the mucosa is characterized by a series of folds and abundance of absorptive cells (ENTEROCYTES) with MICROVILLI.Mice, Inbred C57BLBacteremia: 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.Multigene Family: 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)Genotype: The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.Blood: The body fluid that circulates in the vascular system (BLOOD VESSELS). Whole blood includes PLASMA and BLOOD CELLS.Cloning, Molecular: 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.Manure: Accumulations of solid or liquid animal excreta usually from stables and barnyards with or without litter material. Its chief application is as a fertilizer. (From Webster's 3d ed)ArabinoseMembrane Transport Proteins: Membrane proteins whose primary function is to facilitate the transport of molecules across a biological membrane. Included in this broad category are proteins involved in active transport (BIOLOGICAL TRANSPORT, ACTIVE), facilitated transport and ION CHANNELS.Trans-Activators: Diffusible gene products that act on homologous or heterologous molecules of viral or cellular DNA to regulate the expression of proteins.Multilocus Sequence Typing: Direct nucleotide sequencing of gene fragments from multiple housekeeping genes for the purpose of phylogenetic analysis, organism identification, and typing of species, strain, serovar, or other distinguishable phylogenetic level.Promoter Regions, Genetic: 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.Epithelial Cells: 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.Turkeys: Large woodland game BIRDS in the subfamily Meleagridinae, family Phasianidae, order GALLIFORMES. Formerly they were considered a distinct family, Melegrididae.Carbon-Sulfur Lyases: Enzymes that catalyze the cleavage of a carbon-sulfur bond by means other than hydrolysis or oxidation. EC 4.4.Genetic Variation: Genotypic differences observed among individuals in a population.Caco-2 Cells: Human colonic ADENOCARCINOMA cells that are able to express differentiation features characteristic of mature intestinal cells, such as ENTEROCYTES. These cells are valuable in vitro tools for studies related to intestinal cell function and differentiation.Periplasmic Proteins: Proteins found in the PERIPLASM of organisms with cell walls.UruguayStreptomycin: An antibiotic produced by the soil actinomycete Streptomyces griseus. It acts by inhibiting the initiation and elongation processes during protein synthesis.Porins: Porins are protein molecules that were originally found in the outer membrane of GRAM-NEGATIVE BACTERIA and that form multi-meric channels for the passive DIFFUSION of WATER; IONS; or other small molecules. Porins are present in bacterial CELL WALLS, as well as in plant, fungal, mammalian and other vertebrate CELL MEMBRANES and MITOCHONDRIAL MEMBRANES.Membrane Proteins: 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.Periplasm: The space between the inner and outer membranes of a cell that is shared with the cell wall.Ileum: The distal and narrowest portion of the SMALL INTESTINE, between the JEJUNUM and the ILEOCECAL VALVE of the LARGE INTESTINE.Hafnia alvei: The type species for the genus HAFNIA. It is distinguished from other biochemically similar bacteria by its lack of acid production on media containing sucrose. (From Bergey's Manual of Determinative Bacteriology, 9th ed)Tricarboxylic Acids: Organic compounds that are acyclic and contain three acid groups. A member of this class is citric acid which is the first product formed by reaction of pyruvate and oxaloacetate. (From Lehninger, Principles of Biochemistry, 1982, p443)Transcription, Genetic: The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.Escherichia coli K12: A species of gram-negative, rod-shaped bacteria belonging to the K serogroup of ESCHERICHIA COLI. It lives as a harmless inhabitant of the human LARGE INTESTINE and is widely used in medical and GENETIC RESEARCH.Toll-Like Receptor 5: A pattern recognition receptor that binds FLAGELLIN. It mediates cellular responses to certain bacterial pathogens.Triclosan: A diphenyl ether derivative used in cosmetics and toilet soaps as an antiseptic. It has some bacteriostatic and fungistatic action.Minisatellite Repeats: Tandem arrays of moderately repetitive, short (10-60 bases) DNA sequences which are found dispersed throughout the GENOME, at the ends of chromosomes (TELOMERES), and clustered near telomeres. Their degree of repetition is two to several hundred at each locus. Loci number in the thousands but each locus shows a distinctive repeat unit.Chloramphenicol: An antibiotic first isolated from cultures of Streptomyces venequelae in 1947 but now produced synthetically. It has a relatively simple structure and was the first broad-spectrum antibiotic to be discovered. It acts by interfering with bacterial protein synthesis and is mainly bacteriostatic. (From Martindale, The Extra Pharmacopoeia, 29th ed, p106)Water Microbiology: The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.Disease Models, Animal: 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.Food Storage: Keeping food for later consumption.Reptiles: Cold-blooded, air-breathing VERTEBRATES belonging to the class Reptilia, usually covered with external scales or bony plates.Adhesins, Bacterial: 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.Chromosome Mapping: Any method used for determining the location of and relative distances between genes on a chromosome.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Gene Knockout Techniques: 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.Citrobacter freundii: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria found in humans and other animals including MAMMALS; BIRDS; REPTILES; and AMPHIBIANS. It has also been isolated from SOIL and WATER as well as from clinical specimens such as URINE; THROAT; SPUTUM; BLOOD; and wound swabs as an opportunistic pathogen.Hedgehogs: The family Erinaceidae, in the order INSECTIVORA. Most are true hedgehogs possessing a coat of spines and a very short tail. Those members of the family found in Southeast Asia (moonrats or gymnures) have normal body hair and a long tail.Immunoglobulin A: Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory IgA (IMMUNOGLOBULIN A, SECRETORY) is the main immunoglobulin in secretions.Mutagenicity Tests: Tests of chemical substances and physical agents for mutagenic potential. They include microbial, insect, mammalian cell, and whole animal tests.Gene Expression Profiling: The determination of the pattern of genes expressed at the level of GENETIC TRANSCRIPTION, under specific circumstances or in a specific cell.Evolution, Molecular: The process of cumulative change at the level of DNA; RNA; and PROTEINS, over successive generations.Food Preservatives: Substances capable of inhibiting, retarding or arresting the process of fermentation, acidification or other deterioration of foods.Lethal Dose 50: The dose amount of poisonous or toxic substance or dose of ionizing radiation required to kill 50% of the tested population.NepalImmunity, Mucosal: Nonsusceptibility to the pathogenic effects of foreign microorganisms or antigenic substances as a result of antibody secretions of the mucous membranes. Mucosal epithelia in the gastrointestinal, respiratory, and reproductive tracts produce a form of IgA (IMMUNOGLOBULIN A, SECRETORY) that serves to protect these ports of entry into the body.