Fluoroquinolones: A group of QUINOLONES with at least one fluorine atom and a piperazinyl group.Anti-Infective Agents: Substances that prevent infectious agents or organisms from spreading or kill infectious agents in order to prevent the spread of infection.Ciprofloxacin: A broad-spectrum antimicrobial carboxyfluoroquinoline.Ofloxacin: A synthetic fluoroquinolone antibacterial agent that inhibits the supercoiling activity of bacterial DNA GYRASE, halting DNA REPLICATION.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.Aza CompoundsLevofloxacin: The L-isomer of Ofloxacin.Microbial Sensitivity Tests: Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).DNA Topoisomerase IV: 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. Topoisomerase IV binds to DNA as a heterotetramer consisting 2 parC and 2 parE subunits. Topoisomerase IV is a decatenating enzyme that resolves interlinked daughter chromosomes following DNA replication.Quinolones: A group of derivatives of naphthyridine carboxylic acid, quinoline carboxylic acid, or NALIDIXIC ACID.Norfloxacin: A synthetic fluoroquinolone (FLUOROQUINOLONES) with broad-spectrum antibacterial activity against most gram-negative and gram-positive bacteria. Norfloxacin inhibits bacterial DNA GYRASE.Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.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).Pefloxacin: A synthetic broad-spectrum fluoroquinolone antibacterial agent active against most gram-negative and gram-positive bacteria.NaphthyridinesQuinolinesEnoxacin: A broad-spectrum 6-fluoronaphthyridinone antibacterial agent that is structurally related to NALIDIXIC ACID.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).4-Quinolones: QUINOLONES containing a 4-oxo (a carbonyl in the para position to the nitrogen). They inhibit the A subunit of DNA GYRASE and are used as antimicrobials. Second generation 4-quinolones are also substituted with a 1-piperazinyl group at the 7-position and a fluorine at the 6-position.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 Topoisomerases, Type II: DNA TOPOISOMERASES that catalyze ATP-dependent breakage of both strands of DNA, passage of the unbroken strands through the breaks, and rejoining of the broken strands. These enzymes bring about relaxation of the supercoiled DNA and resolution of a knotted circular DNA duplex.Streptococcus pneumoniae: 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.Dermatitis, Phototoxic: A nonimmunologic, chemically induced type of photosensitivity producing a sometimes vesiculating dermatitis. It results in hyperpigmentation and desquamation of the light-exposed areas of the skin.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.Topoisomerase II Inhibitors: Compounds that inhibit the activity of DNA TOPOISOMERASE II. Included in this category are a variety of ANTINEOPLASTIC AGENTS which target the eukaryotic form of topoisomerase II and ANTIBACTERIAL AGENTS which target the prokaryotic form of topoisomerase II.Gram-Negative Bacterial Infections: Infections caused by bacteria that show up as pink (negative) when treated by the gram-staining method.Macrolides: A group of often glycosylated macrocyclic compounds formed by chain extension of multiple PROPIONATES cyclized into a large (typically 12, 14, or 16)-membered lactone. Macrolides belong to the POLYKETIDES class of natural products, and many members exhibit ANTIBIOTIC properties.Fleroxacin: A broad-spectrum antimicrobial fluoroquinolone. The drug strongly inhibits the DNA-supercoiling activity of DNA GYRASE.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.Mycoplasma hominis: A common inhabitant of the vagina and cervix and a potential human pathogen, causing infections of the male and female reproductive tracts. It has also been associated with respiratory disease and pharyngitis. (From Dorland, 28th ed)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.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.Pneumococcal Infections: Infections with bacteria of the species STREPTOCOCCUS PNEUMONIAE.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.Bacterial Infections: Infections by bacteria, general or unspecified.Typhoid Fever: An acute systemic febrile infection caused by SALMONELLA TYPHI, a serotype of SALMONELLA ENTERICA.Mycobacterium fortuitum: A rapid-growing, nonphotochromogenic species that is potentially pathogenic, producing lesions of lung, bone, or soft tissue following trauma. It has been found in soil and in injection sites of humans, cattle, and cold-blooded animals. (Dorland, 28th ed)Gram-Negative Bacteria: Bacteria which lose crystal violet stain but are stained pink when treated by Gram's method.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.Nitrofurantoin: A urinary anti-infective agent effective against most gram-positive and gram-negative organisms. Although sulfonamides and antibiotics are usually the agents of choice for urinary tract infections, nitrofurantoin is widely used for prophylaxis and long-term suppression.Aminoglycosides: Glycosylated compounds in which there is an amino substituent on the glycoside. Some of them are clinically important ANTIBIOTICS.Pseudomonas aeruginosa: 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.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Gram-Positive Bacteria: Bacteria which retain the crystal violet stain when treated by Gram's method.Capreomycin: Cyclic peptide antibiotic similar to VIOMYCIN. It is produced by Streptomyces capreolus.Community-Acquired Infections: Any infection acquired in the community, that is, contrasted with those acquired in a health care facility (CROSS INFECTION). An infection would be classified as community-acquired if the patient had not recently been in a health care facility or been in contact with someone who had been recently in a health care facility.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.Drug Resistance, Multiple: Simultaneous resistance to several structurally and functionally distinct drugs.Drug Utilization: The utilization of drugs as reported in individual hospital studies, FDA studies, marketing, or consumption, etc. This includes drug stockpiling, and patient drug profiles.Urinary Tract Infections: Inflammatory responses of the epithelium of the URINARY TRACT to microbial invasions. They are often bacterial infections with associated BACTERIURIA and PYURIA.Bacterial Proteins: Proteins found in any species of bacterium.Escherichia coli Infections: Infections with bacteria of the species ESCHERICHIA COLI.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.Paratyphoid Fever: A prolonged febrile illness commonly caused by several Paratyphi serotypes of SALMONELLA ENTERICA. It is similar to TYPHOID FEVER but less severe.Neisseria gonorrhoeae: A species of gram-negative, aerobic bacteria primarily found in purulent venereal discharges. It is the causative agent of GONORRHEA.Cross Infection: Any infection which a patient contracts in a health-care institution.Anti-Infective Agents, Urinary: Substances capable of killing agents causing urinary tract infections or of preventing them from spreading.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.Salmonella typhi: A serotype of SALMONELLA ENTERICA which is the etiologic agent of TYPHOID FEVER.Laurus: A plant genus in the LAURACEAE family. Laurus nobilis L. leaves are known for use in SPICES, having a similar flavor as UMBELLULARIA.Bartonella bacilliformis: The type species of the genus BARTONELLA, a gram-negative bacteria found in humans. It is found in the mountain valleys of Peru, Ecuador, and Southwest Columbia where the sandfly (see PHLEBOTOMUS) vector is present. It causes OROYA FEVER and VERRUGA PERUANA.Gram-Positive Cocci: Coccus-shaped bacteria that retain the crystal violet stain when treated by Gram's method.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.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.Campylobacter: A genus of bacteria found in the reproductive organs, intestinal tract, and oral cavity of animals and man. Some species are pathogenic.Moraxella (Branhamella) catarrhalis: Gram-negative aerobic cocci of low virulence that colonize the nasopharynx and occasionally cause MENINGITIS; BACTEREMIA; EMPYEMA; PERICARDITIS; and PNEUMONIA.Gram-Positive Bacterial Infections: Infections caused by bacteria that retain the crystal violet stain (positive) when treated by the gram-staining method.Otitis Externa: Inflammation of the OUTER EAR including the external EAR CANAL, cartilages of the auricle (EAR CARTILAGE), and the TYMPANIC MEMBRANE.Gonorrhea: Acute infectious disease characterized by primary invasion of the urogenital tract. The etiologic agent, NEISSERIA GONORRHOEAE, was isolated by Neisser in 1879.Respiratory Tract Infections: Invasion of the host RESPIRATORY SYSTEM by microorganisms, usually leading to pathological processes or diseases.Klebsiella pneumoniae: Gram-negative, non-motile, capsulated, gas-producing rods found widely in nature and associated with urinary and respiratory infections in humans.Salmonella paratyphi A: A serotype of SALMONELLA ENTERICA that causes mild PARATYPHOID FEVER in humans.Salmonella enterica: A subgenus of Salmonella containing several medically important serotypes. The habitat for the majority of strains is warm-blooded animals.Bacteria, AnaerobicTrimethoprim-Sulfamethoxazole Combination: This drug combination has proved to be an effective therapeutic agent with broad-spectrum antibacterial activity against both gram-positive and gram-negative organisms. It is effective in the treatment of many infections, including PNEUMOCYSTIS PNEUMONIA in AIDS.Tetracyclines: Closely congeneric derivatives of the polycyclic naphthacenecarboxamide. (Gilman et al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed, p1117)Campylobacter Infections: Infections with bacteria of the genus CAMPYLOBACTER.Carbapenems: A group of beta-lactam antibiotics in which the sulfur atom in the thiazolidine ring of the penicillin molecule is replaced by a carbon atom. THIENAMYCINS are a subgroup of carbapenems which have a sulfur atom as the first constituent of the side chain.beta-Lactam Resistance: Nonsusceptibility of bacteria to the action of the beta-lactam antibiotics. Mechanisms responsible for beta-lactam resistance may be degradation of antibiotics by BETA-LACTAMASES, failure of antibiotics to penetrate, or low-affinity binding of antibiotics to targets.Extensively Drug-Resistant Tuberculosis: Tuberculosis resistant to ISONIAZID and RIFAMPIN and at least three of the six main classes of second-line drugs (AMINOGLYCOSIDES; polypeptide agents; FLUOROQUINOLONES; THIOAMIDES; CYCLOSERINE; and PARA-AMINOSALICYLIC ACID) as defined by the CDC.Chromatography, Supercritical Fluid: A CHROMATOGRAPHY method using supercritical fluid, usually carbon dioxide under very high pressure (around 73 atmospheres or 1070 psi at room temperature) as the mobile phase. Other solvents are sometimes added as modifiers. This is used both for analytical (SFC) and extraction (SFE) purposes.Clostridium Infections: Infections with bacteria of the genus CLOSTRIDIUM.Serum Bactericidal Test: Method of measuring the bactericidal activity contained in a patient's serum as a result of antimicrobial therapy. It is used to monitor the therapy in BACTERIAL ENDOCARDITIS; OSTEOMYELITIS and other serious bacterial infections. As commonly performed, the test is a variation of the broth dilution test. This test needs to be distinguished from testing of the naturally occurring BLOOD BACTERICIDAL ACTIVITY.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.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.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)DioxolanesRibotyping: RESTRICTION FRAGMENT LENGTH POLYMORPHISM analysis of rRNA genes that is used for differentiating between species or strains.Area Under Curve: A statistical means of summarizing information from a series of measurements on one individual. It is frequently used in clinical pharmacology where the AUC from serum levels can be interpreted as the total uptake of whatever has been administered. As a plot of the concentration of a drug against time, after a single dose of medicine, producing a standard shape curve, it is a means of comparing the bioavailability of the same drug made by different companies. (From Winslade, Dictionary of Clinical Research, 1992)Lactams: Cyclic AMIDES formed from aminocarboxylic acids by the elimination of water. Lactims are the enol forms of lactams.Bacteroides fragilis: Gram-negative bacteria occurring in the lower intestinal tracts of man and other animals. It is the most common species of anaerobic bacteria isolated from human soft tissue infections.Genes, Bacterial: The functional hereditary units of BACTERIA.Erythromycin: A bacteriostatic antibiotic macrolide produced by Streptomyces erythreus. Erythromycin A is considered its major active component. In sensitive organisms, it inhibits protein synthesis by binding to 50S ribosomal subunits. This binding process inhibits peptidyl transferase activity and interferes with translocation of amino acids during translation and assembly of proteins.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.Pseudomonas Infections: Infections with bacteria of the genus PSEUDOMONAS.Eye Infections, Bacterial: Infections in the inner or external eye caused by microorganisms belonging to several families of bacteria. Some of the more common genera found are Haemophilus, Neisseria, Staphylococcus, Streptococcus, and Chlamydia.Campylobacter jejuni: A species of bacteria that resemble small tightly coiled spirals. Its organisms are known to cause abortion in sheep and fever and enteritis in man and may be associated with enteric diseases of calves, lambs, and other animals.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.Ketolides: Compounds based on ERYTHROMYCIN with the 3-cladinose replaced by a ketone. They bind the 23S part of 70S bacterial RIBOSOMES.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.Minocycline: A TETRACYCLINE analog, having a 7-dimethylamino and lacking the 5 methyl and hydroxyl groups, which is effective against tetracycline-resistant STAPHYLOCOCCUS infections.Membrane 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.Dermatitis, Photoallergic: A delayed hypersensitivity involving the reaction between sunlight or other radiant energy source and a chemical substance to which the individual has been previously exposed and sensitized. It manifests as a papulovesicular, eczematous, or exudative dermatitis occurring chiefly on the light-exposed areas of the skin.Hospitals: Institutions with an organized medical staff which provide medical care to patients.Staphylococcal Infections: Infections with bacteria of the genus STAPHYLOCOCCUS.DNA Topoisomerases: Enzymes that regulate the topology of DNA by actions such as breaking, relaxing, passing, and rejoining strands of DNA in cells. These enzymes are important components of the DNA replication system. They are classified by their substrate specificities. DNA TOPOISOMERASE I enzymes act on a single strand of DNA. DNA TOPOISOMERASE II enzymes act on double strands of DNA.Cephalosporin Resistance: Non-susceptibility of an organism to the action of the cephalosporins.Klebsiella Infections: Infections with bacteria of the genus KLEBSIELLA.Salmonella Infections: Infections with bacteria of the genus SALMONELLA.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)Pneumonia, Bacterial: Inflammation of the lung parenchyma that is caused by bacterial infections.Acinetobacter: A genus of gram-negative bacteria of the family MORAXELLACEAE, found in soil and water and of uncertain pathogenicity.Bacteremia: 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.Ethidium: A trypanocidal agent and possible antiviral agent that is widely used in experimental cell biology and biochemistry. Ethidium has several experimentally useful properties including binding to nucleic acids, noncompetitive inhibition of nicotinic acetylcholine receptors, and fluorescence among others. It is most commonly used as the bromide.Streptogramin B: A specific streptogramin group B antibiotic produced by Streptomyces graminofaciens and other bacteria.Reserpine: An alkaloid found in the roots of Rauwolfia serpentina and R. vomitoria. Reserpine inhibits the uptake of norepinephrine into storage vesicles resulting in depletion of catecholamines and serotonin from central and peripheral axon terminals. It has been used as an antihypertensive and an antipsychotic as well as a research tool, but its adverse effects limit its clinical use.Tendinopathy: Clinical syndrome describing overuse tendon injuries characterized by a combination of PAIN, diffuse or localized swelling, and impaired performance. Distinguishing tendinosis from tendinitis is clinically difficult and can be made only after histopathological examination.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Campylobacter coli: A species of gram-negative, rod-shaped bacteria isolated from the intestinal tract of swine, poultry, and man. It may be pathogenic.Achilles Tendon: A fibrous cord that connects the muscles in the back of the calf to the HEEL BONE.Enterobacteriaceae Infections: Infections with bacteria of the family ENTEROBACTERIACEAE.Drug Interactions: The action of a drug that may affect the activity, metabolism, or toxicity of another drug.Haemophilus influenzae: A species of HAEMOPHILUS found on the mucous membranes of humans and a variety of animals. The species is further divided into biotypes I through VIII.Shigella sonnei: A lactose-fermenting bacterium causing dysentery.Bronchitis, Chronic: A subcategory of CHRONIC OBSTRUCTIVE PULMONARY DISEASE. The disease is characterized by hypersecretion of mucus accompanied by a chronic (more than 3 months in 2 consecutive years) productive cough. Infectious agents are a major cause of chronic bronchitis.Tetracycline: A naphthacene antibiotic that inhibits AMINO ACYL TRNA binding during protein synthesis.Mycoplasma bovis: A species of gram-negative bacteria causing MASTITIS; ARTHRITIS; and RESPIRATORY TRACT DISEASES in CATTLE.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)Mycobacterium smegmatis: A rapid-growing, nonphotochromogenic species of MYCOBACTERIUM originally isolated from human smegma and found also in soil and water. (From Dorland, 28th ed)Stenotrophomonas maltophilia: A species of STENOTROPHOMONAS, formerly called Xanthomonas maltophilia, which reduces nitrate. It is a cause of hospital-acquired ocular and lung infections, especially in those patients with cystic fibrosis and those who are immunosuppressed.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.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.Azithromycin: A semi-synthetic macrolide antibiotic structurally related to ERYTHROMYCIN. It has been used in the treatment of Mycobacterium avium intracellulare infections, toxoplasmosis, and cryptosporidiosis.Methicillin Resistance: Non-susceptibility of a microbe to the action of METHICILLIN, a semi-synthetic penicillin derivative.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.Enterobacter cloacae: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that occurs in water, sewage, soil, meat, hospital environments, and on the skin and in the intestinal tract of man and animals as a commensal.