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.

Community of tiny aquatic PLANTS and ANIMALS, and photosynthetic BACTERIA, that are either free-floating or suspended in the water, with little or no power of locomotion. They are divided into PHYTOPLANKTON and ZOOPLANKTON.

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.

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.

Ability of a microbe to survive under given conditions. This can also be related to a colony's ability to replicate.

Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.

Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.

Proteins found in any species of bacterium.

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.

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.

A polysaccharide-producing species of STREPTOCOCCUS isolated from human dental plaque.

Physiological processes and properties of BACTERIA.

A unicellular budding fungus which is the principal pathogenic species causing CANDIDIASIS (moniliasis).

A species of gram-positive, coccoid bacteria that is numerous in the mouth and throat. It is a common cause of endocarditis and is also implicated in dental plaque formation.

A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.

Substances that reduce the growth or reproduction of BACTERIA.

Polysaccharides found in bacteria and in capsules thereof.

A species of STAPHYLOCOCCUS that is a spherical, non-motile, gram-positive, chemoorganotrophic, facultative anaerobe. Mainly found on the skin and mucous membrane of warm-blooded animals, it can be primary pathogen or secondary invader.

One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.

The inter- and intra-relationships between various microorganisms. This can include both positive (like SYMBIOSIS) and negative (like ANTIBIOSIS) interactions. Examples include virus - bacteria and bacteria - bacteria.

A film that attaches to teeth, often causing DENTAL CARIES and GINGIVITIS. It is composed of MUCINS, secreted from salivary glands, and microorganisms.

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.

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)

Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).

Cationic bactericidal surfactant used as a topical antiseptic for skin, wounds, mucous membranes, instruments, etc.; and also as a component in mouthwash and lozenges.

The presence of an infectious agent on instruments, prostheses, or other inanimate articles.

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.

Polymerized forms of styrene used as a biocompatible material, especially in dentistry. They are thermoplastic and are used as insulators, for injection molding and casting, as sheets, plates, rods, rigid forms and beads.

The oval-shaped oral cavity located at the apex of the digestive tract and consisting of two parts: the vestibule and the oral cavity proper.

Tools or devices for generating products using the synthetic or chemical conversion capacity of a biological system. They can be classical fermentors, cell culture perfusion systems, or enzyme bioreactors. For production of proteins or enzymes, recombinant microorganisms such as bacteria, mammalian cells, or insect or plant cells are usually chosen.

A disinfectant and topical anti-infective agent used also as mouthwash to prevent oral plaque.

Ionized gases, consisting of free electrons and ionized atoms or molecules which collectively behave differently than gas, solid, or liquid. Plasma gases are used in biomedical fields in surface modification; biological decontamination; dentistry (e.g., PLASMA ARC DENTAL CURING LIGHTS); and in other treatments (e.g., ARGON PLASMA COAGULATION).

Stainless steel. A steel containing Ni, Cr, or both. It does not tarnish on exposure and is used in corrosive environments. (Grant & Hack's Chemical Dictionary, 5th ed)

A polyvinyl resin used extensively in the manufacture of plastics, including medical devices, tubing, and other packaging. It is also used as a rubber substitute.

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.

A liquid that functions as a strong oxidizing agent. It has an acrid odor and is used as a disinfectant.

A genus of gram-positive, rod-shaped bacteria whose organisms are nonmotile. Filaments that may be present in certain species are either straight or wavy and may have swollen or clubbed heads.

An aminoglycoside, broad-spectrum antibiotic produced by Streptomyces tenebrarius. It is effective against gram-negative bacteria, especially the PSEUDOMONAS species. It is a 10% component of the antibiotic complex, NEBRAMYCIN, produced by the same species.

Substances used on humans and other animals that destroy harmful microorganisms or inhibit their activity. They are distinguished from DISINFECTANTS, which are used on inanimate objects.

Substances that destroy fungi by suppressing their ability to grow or reproduce. They differ from FUNGICIDES, INDUSTRIAL because they defend against fungi present in human or animal tissues.

Infections resulting from the use of catheters. Proper aseptic technique, site of catheter placement, material composition, and virulence of the organism are all factors that can influence possible infection.

Homoserine is a non-proteinogenic amino acid, an intermediate in the biosynthesis of certain amino acids and other metabolites, with structural formula (2S)-2-amino-1-hydroxybutane-1-carboxylic acid.

Deoxyribonucleic acid that makes up the genetic material of bacteria.

The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.

A species of gram-positive, facultatively anaerobic bacteria in the family STREPTOCOCCACEAE. It is a normal inhabitant of the human oral cavity, and causes DENTAL PLAQUE and ENDOCARDITIS. It is being investigated as a vehicle for vaccine delivery.

A colorless liquid extracted from oils of plants such as citronella, neroli, cyclamen, and tuberose. It is an intermediate step in the biological synthesis of cholesterol from mevalonic acid in vertebrates. It has a delicate odor and is used in perfumery. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)

Polymers of silicone that are formed by crosslinking and treatment with amorphous silica to increase strength. They have properties similar to vulcanized natural rubber, in that they stretch under tension, retract rapidly, and fully recover to their original dimensions upon release. They are used in the encapsulation of surgical membranes and implants.

Electric power supply devices which convert biological energy, such as chemical energy of metabolism or mechanical energy of periodic movements, into electrical energy.

A species of gram-negative, anaerobic, rod-shaped bacteria isolated from the gingival margin and sulcus and from infections of the upper respiratory tract and pleural cavity.

Measurable quantity of bacteria in an object, organism, or organism compartment.

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).

Characteristics or attributes of the outer boundaries of objects, including molecules.

A group of different species of microorganisms that act together as a community.

A dye that is a mixture of violet rosanilinis with antibacterial, antifungal, and anthelmintic properties.

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 flexible, tubular device that is used to carry fluids into or from a blood vessel, hollow organ, or body cavity.

Total mass of all the organisms of a given type and/or in a given area. (From Concise Dictionary of Biology, 1990) It includes the yield of vegetative mass produced from any given crop.

Enzymes that catalyze the cleavage of a carbon-sulfur bond by means other than hydrolysis or oxidation. EC 4.4.

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).

Salts of alginic acid that are extracted from marine kelp and used to make dental impressions and as absorbent material for surgical dressings.

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.

A broad family of synthetic organosiloxane polymers containing a repeating silicon-oxygen backbone with organic side groups attached via carbon-silicon bonds. Depending on their structure, they are classified as liquids, gels, and elastomers. (From Merck Index, 12th ed)

A species of gram-positive, coccoid bacteria commonly isolated from clinical specimens and the human intestinal tract. Most strains are nonhemolytic.

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 genus of gram-negative, anaerobic cocci parasitic in the mouth and in the intestinal and respiratory tracts of man and other animals.

The ability of fungi to resist or to become tolerant to chemotherapeutic agents, antifungal agents, or antibiotics. This resistance may be acquired through gene mutation.

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.

A species of gram-negative bacteria in the genus ALIIVIBRIO, which exhibits LUMINESCENCE. A. fischeri is found in a symbiotic relationship with the SQUID Euprymna scolopes.

A species of nonpathogenic fluorescent bacteria found in feces, sewage, soil, and water, and which liquefy gelatin.

A thin protein film on the surface of DENTAL ENAMEL. It is widely believed to result from the selective adsorption of precursor proteins present in SALIVA onto tooth surfaces, and to reduce microbial adherence to the TEETH.

Hard, amorphous, brittle, inorganic, usually transparent, polymerous silicate of basic oxides, usually potassium or sodium. It is used in the form of hard sheets, vessels, tubing, fibers, ceramics, beads, etc.

Enzymes that catalyze the cleavage of a phosphorus-oxygen bond by means other than hydrolysis or oxidation. EC 4.6.

Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.

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)

A genus of yeast-like mitosporic Saccharomycetales fungi characterized by producing yeast cells, mycelia, pseudomycelia, and blastophores. It is commonly part of the normal flora of the skin, mouth, intestinal tract, and vagina, but can cause a variety of infections, including CANDIDIASIS; ONYCHOMYCOSIS; vulvovaginal candidiasis (CANDIDIASIS, VULVOVAGINAL), and thrush (see CANDIDIASIS, ORAL). (From Dorland, 28th ed)

Infections with bacteria of the genus PSEUDOMONAS.

Expendable and nonexpendable equipment, supplies, apparatus, and instruments that are used in diagnostic, surgical, therapeutic, scientific, and experimental procedures.

Infections with bacteria of the genus STAPHYLOCOCCUS.

The functional hereditary units of BACTERIA.

Techniques used in studying bacteria.

An acid dye used in testing for hydrochloric acid in gastric contents. It is also used histologically to test for AMYLOIDOSIS.

Viruses whose host is Pseudomonas. A frequently encountered Pseudomonas phage is BACTERIOPHAGE PHI 6.

Term used to designate tetrahydroxy aldehydic acids obtained by oxidation of hexose sugars, i.e. glucuronic acid, galacturonic acid, etc. Historically, the name hexuronic acid was originally given to ascorbic acid.

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.

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.

Cyclic hexapeptides of proline-ornithine-threonine-proline-threonine-serine. The cyclization with a single non-peptide bond can lead them to be incorrectly called DEPSIPEPTIDES, but the echinocandins lack ester links. Antifungal activity is via inhibition of 1,3-beta-glucan synthase production of BETA-GLUCANS.

Rendering pathogens harmless through the use of heat, antiseptics, antibacterial agents, etc.

A species of gram-negative, aerobic bacteria isolated from soil and water as well as clinical specimens. Occasionally it is an opportunistic pathogen.

A genus of gram-negative, facultatively anaerobic rods. It is a saprophytic, marine organism which is often isolated from spoiling fish.

Inflammation of the mouth due to denture irritation.

A sugar acid formed by the oxidation of the C-6 carbon of GLUCOSE. In addition to being a key intermediate metabolite of the uronic acid pathway, glucuronic acid also plays a role in the detoxification of certain drugs and toxins by conjugating with them to form GLUCURONIDES.

Microscopic threadlike filaments in FUNGI that are filled with a layer of protoplasm. Collectively, the hyphae make up the MYCELIUM.

A genus of GRAM-NEGATIVE AEROBIC BACTERIA of marine origin. Many species were formerly classified under ALTEROMONAS.

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.

Quaternary salts derived from tetrazoles. They are used in tests to distinguish between reducing sugars and simple aldehydes, for detection of dehydrogenase in tissues, cells, and bacteria, for determination of corticosteroids, and in color photography. (From Mall's Dictionary of Chemistry, 5th ed, p455)

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.

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 etiologic agent of CHOLERA.

Triazole antifungal agent that is used to treat oropharyngeal CANDIDIASIS and cryptococcal MENINGITIS in AIDS.

A genus of gram-negative, aerobic bacteria, in the family XANTHOMONADACEAE. It is found in the xylem of plant tissue.

Substances that prevent infectious agents or organisms from spreading or kill infectious agents in order to prevent the spread of infection.

Catheters designed to be left within an organ or passage for an extended period of time.

The clear, viscous fluid secreted by the SALIVARY GLANDS and mucous glands of the mouth. It contains MUCINS, water, organic salts, and ptylin.

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.

The study of microorganisms living in a variety of environments (air, soil, water, etc.) and their pathogenic relationship to other organisms including man.

Rupture of bacterial cells due to mechanical force, chemical action, or the lytic growth of BACTERIOPHAGES.

Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.

Cyclic esters of acylated BUTYRIC ACID containing four carbons in the ring.

Glucose polymers consisting of a backbone of beta(1->3)-linked beta-D-glucopyranosyl units with beta(1->6) linked side chains of various lengths. They are a major component of the CELL WALL of organisms and of soluble DIETARY FIBER.

The marking of biological material with a dye or other reagent for the purpose of identifying and quantitating components of tissues, cells or their extracts.

A broad-spectrum antimicrobial carboxyfluoroquinoline.

Means or process of supplying water (as for a community) usually including reservoirs, tunnels, and pipelines and often the watershed from which the water is ultimately drawn. (Webster, 3d ed)

A mixture of alkylbenzyldimethylammonium compounds. It is a bactericidal quaternary ammonium detergent used topically in medicaments, deodorants, mouthwashes, as a surgical antiseptic, and as a as preservative and emulsifier in drugs and cosmetics.

Proteins that are structural components of bacterial fimbriae (FIMBRIAE, BACTERIAL) or sex pili (PILI, SEX).

Cyclic esters of hydroxy carboxylic acids, containing a 1-oxacycloalkan-2-one structure. Large cyclic lactones of over a dozen atoms are MACROLIDES.

The physical effects involving the presence of electric charges at rest and in motion.

A species of gram-negative bacteria that causes disease in plants. It is found commonly in the environment and is an opportunistic pathogen in humans.

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.

Antibacterial obtained from Streptomyces orientalis. It is a glycopeptide related to RISTOCETIN that inhibits bacterial cell wall assembly and is toxic to kidneys and the inner ear.

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.

The spectrum of different living organisms inhabiting a particular region, habitat, or biotope.

Macrolide antifungal antibiotic produced by Streptomyces nodosus obtained from soil of the Orinoco river region of Venezuela.

An autolytic enzyme bound to the surface of bacterial cell walls. It catalyzes the hydrolysis of the link between N-acetylmuramoyl residues and L-amino acid residues in certain cell wall glycopeptides, particularly peptidoglycan. EC 3.5.1.28.

Water containing no significant amounts of salts, such as water from RIVERS and LAKES.

Large natural streams of FRESH WATER formed by converging tributaries and which empty into a body of water (lake or ocean).