Streptomycin: An antibiotic produced by the soil actinomycete Streptomyces griseus. It acts by inhibiting the initiation and elongation processes during protein synthesis.Dihydrostreptomycin Sulfate: A semi-synthetic aminoglycoside antibiotic that is used in the treatment of TUBERCULOSIS.Streptomyces griseus: An actinomycete from which the antibiotics STREPTOMYCIN, grisein, and CANDICIDIN are obtained.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).Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.Kanamycin: Antibiotic complex produced by Streptomyces kanamyceticus from Japanese soil. Comprises 3 components: kanamycin A, the major component, and kanamycins B and C, the minor components.Spectinomycin: An antibiotic produced by Streptomyces spectabilis. It is active against gram-negative bacteria and used for the treatment of gonorrhea.R Factors: A class of plasmids that transfer antibiotic resistance from one bacterium to another by conjugation.Microbial Sensitivity Tests: Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).Ethambutol: An antitubercular agent that inhibits the transfer of mycolic acids into the cell wall of the tubercle bacillus. It may also inhibit the synthesis of spermidine in mycobacteria. The action is usually bactericidal, and the drug can penetrate human cell membranes to exert its lethal effect. (From Smith and Reynard, Textbook of Pharmacology, 1992, p863)Antitubercular Agents: Drugs used in the treatment of tuberculosis. They are divided into two main classes: "first-line" agents, those with the greatest efficacy and acceptable degrees of toxicity used successfully in the great majority of cases; and "second-line" drugs used in drug-resistant cases or those in which some other patient-related condition has compromised the effectiveness of primary therapy.Aminoglycosides: Glycosylated compounds in which there is an amino substituent on the glycoside. Some of them are clinically important ANTIBIOTICS.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.Rifampin: A semisynthetic antibiotic produced from Streptomyces mediterranei. It has a broad antibacterial spectrum, including activity against several forms of Mycobacterium. In susceptible organisms it inhibits DNA-dependent RNA polymerase activity by forming a stable complex with the enzyme. It thus suppresses the initiation of RNA synthesis. Rifampin is bactericidal, and acts on both intracellular and extracellular organisms. (From Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 9th ed, p1160)Neomycin: Antibiotic complex produced by Streptomyces fradiae. It is composed of neomycins A, B, and C. It acts by inhibiting translation during protein synthesis.Isoniazid: Antibacterial agent used primarily as a tuberculostatic. It remains the treatment of choice for tuberculosis.Tetracycline: A naphthacene antibiotic that inhibits AMINO ACYL TRNA binding during protein synthesis.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)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).Gentamicins: A complex of closely related aminoglycosides obtained from MICROMONOSPORA purpurea and related species. They are broad-spectrum antibiotics, but may cause ear and kidney damage. They act to inhibit PROTEIN BIOSYNTHESIS.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.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).DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Mycobacterium tuberculosis: 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.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.Buruli Ulcer: A lesion in the skin and subcutaneous tissues due to infections by MYCOBACTERIUM ULCERANS. It was first reported in Uganda, Africa.Extrachromosomal Inheritance: Vertical transmission of hereditary characters by DNA from cytoplasmic organelles such as MITOCHONDRIA; CHLOROPLASTS; and PLASTIDS, or from PLASMIDS or viral episomal DNA.Tuberculosis, Multidrug-Resistant: Tuberculosis resistant to chemotherapy with two or more ANTITUBERCULAR AGENTS, including at least ISONIAZID and RIFAMPICIN. The problem of resistance is particularly troublesome in tuberculous OPPORTUNISTIC INFECTIONS associated with HIV INFECTIONS. It requires the use of second line drugs which are more toxic than the first line regimens. TB with isolates that have developed further resistance to at least three of the six classes of second line drugs is defined as EXTENSIVELY DRUG-RESISTANT TUBERCULOSIS.Enterococcus faecalis: A species of gram-positive, coccoid bacteria commonly isolated from clinical specimens and the human intestinal tract. Most strains are nonhemolytic.Ampicillin: Semi-synthetic derivative of penicillin that functions as an orally active broad-spectrum antibiotic.Paromomycin: An oligosaccharide antibiotic produced by various STREPTOMYCES.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.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.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)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.Antibiotics, Antitubercular: Substances obtained from various species of microorganisms that are, alone or in combination with other agents, of use in treating various forms of tuberculosis; most of these agents are merely bacteriostatic, induce resistance in the organisms, and may be toxic.Salmonella Infections, Animal: Infections in animals with bacteria of the genus SALMONELLA.Framycetin: A component of NEOMYCIN that is produced by Streptomyces fradiae. On hydrolysis it yields neamine and neobiosamine B. (From Merck Index, 11th ed)Ribosomes: Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.Bacterial Proteins: Proteins found in any species of bacterium.Streptomyces: A genus of bacteria that form a nonfragmented aerial mycelium. Many species have been identified with some being pathogenic. This genus is responsible for producing a majority of the ANTI-BACTERIAL AGENTS of practical value.Genes, Bacterial: The functional hereditary units of BACTERIA.Brucellosis: Infection caused by bacteria of the genus BRUCELLA mainly involving the MONONUCLEAR PHAGOCYTE SYSTEM. This condition is characterized by fever, weakness, malaise, and weight loss.Streptococcus: 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.Shigella sonnei: A lactose-fermenting bacterium causing dysentery.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.Pharmacology: The study of the origin, nature, properties, and actions of drugs and their effects on living organisms.Penicillin Resistance: Nonsusceptibility of an organism to the action of penicillins.Salmonella typhimurium: A serotype of Salmonella enterica that is a frequent agent of Salmonella gastroenteritis in humans. It also causes PARATYPHOID FEVER.Amidinotransferases: Enzymes of a subclass of TRANSFERASES that catalyze the transfer of an amidino group from donor to acceptor. EC 2.1.4.Salmonella Infections: Infections with bacteria of the genus SALMONELLA.RNA, Bacterial: Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.4-Butyrolactone: 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.Capreomycin: Cyclic peptide antibiotic similar to VIOMYCIN. It is produced by Streptomyces capreolus.Mycobacterium ulcerans: A slow-growing mycobacterium that infects the skin and subcutaneous tissues, giving rise to indolent BURULI ULCER.Bacteriophage Typing: A technique of bacterial typing which differentiates between bacteria or strains of bacteria by their susceptibility to one or more bacteriophages.