Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.Microbial Sensitivity Tests: Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).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.Bacterial Infections: Infections by bacteria, general or unspecified.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).beta-Lactams: Four-membered cyclic AMIDES, best known for the PENICILLINS based on a bicyclo-thiazolidine, as well as the CEPHALOSPORINS based on a bicyclo-thiazine, and including monocyclic MONOBACTAMS. The BETA-LACTAMASES hydrolyze the beta lactam ring, accounting for BETA-LACTAM RESISTANCE of infective bacteria.Bacteria: 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.Metagenome: A collective genome representative of the many organisms, primarily microorganisms, existing in a community.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.Gram-Positive Bacteria: Bacteria which retain the crystal violet stain when treated by Gram's method.Periodicals as Topic: A publication issued at stated, more or less regular, intervals.Access to Information: Individual's rights to obtain and use information collected or generated by others.Mevalonate Kinase Deficiency: Autosomal recessive disorder caused by mutations in the mevalonate kinase gene. Because of the mutations cholesterol biosynthesis is disrupted and MEVALONIC ACID accumulates. It is characterized by a range of symptoms, including dysmorphic FACIES, psychomotor retardation, CATARACT, hepatosplenomegaly, CEREBELLAR ATAXIA, elevated IMMUNOGLOBULIN D, and recurrent febrile crises with FEVER; LYMPHADENOPATHY; ARTHRALGIA; EDEMA; and rash.Journal Impact Factor: A quantitative measure of the frequency on average with which articles in a journal have been cited in a given period of time.Bibliometrics: The use of statistical methods in the analysis of a body of literature to reveal the historical development of subject fields and patterns of authorship, publication, and use. Formerly called statistical bibliography. (from The ALA Glossary of Library and Information Science, 1983)Publishing: "The business or profession of the commercial production and issuance of literature" (Webster's 3d). It includes the publisher, publication processes, editing and editors. Production may be by conventional printing methods or by electronic publishing.Peer Review, Research: The evaluation by experts of the quality and pertinence of research or research proposals of other experts in the same field. Peer review is used by editors in deciding which submissions warrant publication, by granting agencies to determine which proposals should be funded, and by academic institutions in tenure decisions.Mevalonic AcidJournalism, Medical: The collection, writing, and editing of current interest material on topics related to biomedicine for presentation through the mass media, including newspapers, magazines, radio, or television, usually for a public audience such as health care consumers.Phosphotransferases (Alcohol Group Acceptor): A group of enzymes that transfers a phosphate group onto an alcohol group acceptor. EC 2.7.1.Haemophilus somnus: A species of gram-negative bacteria (currently incertae sedis) causing multisystem disease in CATTLE.Clostridium difficile: A common inhabitant of the colon flora in human infants and sometimes in adults. It produces a toxin that causes pseudomembranous enterocolitis (ENTEROCOLITIS, PSEUDOMEMBRANOUS) in patients receiving antibiotic therapy.Spores, Bacterial: Heat and stain resistant, metabolically inactive bodies formed within the vegetative cells of bacteria of the genera Bacillus and Clostridium.Metronidazole: A nitroimidazole used to treat AMEBIASIS; VAGINITIS; TRICHOMONAS INFECTIONS; GIARDIASIS; ANAEROBIC BACTERIA; and TREPONEMAL INFECTIONS. It has also been proposed as a radiation sensitizer for hypoxic cells. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985, p133), this substance may reasonably be anticipated to be a carcinogen (Merck, 11th ed).Spores: The reproductive elements of lower organisms, such as BACTERIA; FUNGI; and cryptogamic plants.Vancomycin: 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.Enterocolitis, Pseudomembranous: An acute inflammation of the INTESTINAL MUCOSA that is characterized by the presence of pseudomembranes or plaques in the SMALL INTESTINE (pseudomembranous enteritis) and the LARGE INTESTINE (pseudomembranous colitis). It is commonly associated with antibiotic therapy and CLOSTRIDIUM DIFFICILE colonization.Clostridium Infections: Infections with bacteria of the genus CLOSTRIDIUM.Spores, Fungal: Reproductive bodies produced by fungi.Clostridium: A genus of motile or nonmotile gram-positive bacteria of the family Clostridiaceae. Many species have been identified with some being pathogenic. They occur in water, soil, and in the intestinal tract of humans and lower animals.Gallium: A rare, metallic element designated by the symbol, Ga, atomic number 31, and atomic weight 69.72.Gallium Radioisotopes: Unstable isotopes of gallium that decay or disintegrate emitting radiation. Ga atoms with atomic weights 63-68, 70 and 72-76 are radioactive gallium isotopes.Newspapers: Publications printed and distributed daily, weekly, or at some other regular and usually short interval, containing news, articles of opinion (as editorials and letters), features, advertising, and announcements of current interest. (Webster's 3d ed)Tooth Preparation: Procedures carried out with regard to the teeth or tooth structures preparatory to specified dental therapeutic and surgical measures.Mass Media: Instruments or technological means of communication that reach large numbers of people with a common message: press, radio, television, etc.Anti-Infective Agents: Substances that prevent infectious agents or organisms from spreading or kill infectious agents in order to prevent the spread of infection.Staphylococcus aureus: 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.Mycobacterium: A genus of gram-positive, aerobic bacteria. Most species are free-living in soil and water, but the major habitat for some is the diseased tissue of warm-blooded hosts.Mycolic AcidsAntigens, Tumor-Associated, Carbohydrate: Carbohydrate antigens expressed by malignant tissue. They are useful as tumor markers and are measured in the serum by means of a radioimmunoassay employing monoclonal antibodies.Cell Wall: 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.Carbohydrates: The largest class of organic compounds, including STARCH; GLYCOGEN; CELLULOSE; POLYSACCHARIDES; and simple MONOSACCHARIDES. Carbohydrates are composed of carbon, hydrogen, and oxygen in a ratio of Cn(H2O)n.PeptidoglycanGlycoconjugates: Carbohydrates covalently linked to a nonsugar moiety (lipids or proteins). The major glycoconjugates are glycoproteins, glycopeptides, peptidoglycans, glycolipids, and lipopolysaccharides. (From Biochemical Nomenclature and Related Documents, 2d ed; From Principles of Biochemistry, 2d ed)Carbohydrate Sequence: The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.Tuberculosis: Any of the infectious diseases of man and other animals caused by species of MYCOBACTERIUM.Monobactams: Monocyclic, bacterially produced or semisynthetic beta-lactam antibiotics. They lack the double ring construction of the traditional beta-lactam antibiotics and can be easily synthesized.Penicillin-Binding Proteins: Bacterial proteins that share the property of binding irreversibly to PENICILLINS and other ANTIBACTERIAL AGENTS derived from LACTAMS. The penicillin-binding proteins are primarily enzymes involved in CELL WALL biosynthesis including MURAMOYLPENTAPEPTIDE CARBOXYPEPTIDASE; PEPTIDE SYNTHASES; TRANSPEPTIDASES; and HEXOSYLTRANSFERASES.Muramoylpentapeptide Carboxypeptidase: Enzyme which catalyzes the peptide cross-linking of nascent CELL WALL; PEPTIDOGLYCAN.Penicillins: A group of antibiotics that contain 6-aminopenicillanic acid with a side chain attached to the 6-amino group. The penicillin nucleus is the chief structural requirement for biological activity. The side-chain structure determines many of the antibacterial and pharmacological characteristics. (Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed, p1065)Lactams: Cyclic AMIDES formed from aminocarboxylic acids by the elimination of water. Lactims are the enol forms of lactams.Hexosyltransferases: Enzymes that catalyze the transfer of hexose groups. EC 2.4.1.-.Cephalosporins: A group of broad-spectrum antibiotics first isolated from the Mediterranean fungus ACREMONIUM. They contain the beta-lactam moiety thia-azabicyclo-octenecarboxylic acid also called 7-aminocephalosporanic acid.Mouth DiseasesDentistry: The profession concerned with the teeth, oral cavity, and associated structures, and the diagnosis and treatment of their diseases including prevention and the restoration of defective and missing tissue.Thalictrum: A plant genus of the family RANUNCULACEAE. Members contain isoquinoline alkaloids and triterpene glycosides.Propiolactone: Disinfectant used in vapor form to sterilize vaccines, grafts, etc. The vapor is very irritating and the liquid form is carcinogenic.Pediatric Dentistry: The practice of dentistry concerned with the dental problems of children, proper maintenance, and treatment. The dental care may include the services provided by dental specialists.Peer Group: Group composed of associates of same species, approximately the same age, and usually of similar rank or social status.