Biomaterial Database

Characterization of spontaneous resistant variants of Serratia marcescens selected in the presence of carbenicillin. 1983

D J Platt, and J S Sommerville, and J A McGroarty

Spontaneous carbenicillin-resistant variants were isolated from pigmented Serratia marcescens GRI 2677 with frequencies as high as 1 in 7.4 x 10(4). One-hundred and thirteen such variants were characterized with respect to pigmentation, antimicrobial susceptibility and beta-lactamase production. Sixty-eight were less pigmented than the parent culture, 84 showed low level resistance to five aminoglycosides and 17 showed increased beta-lactamase activity. Thirty-three variants were unstable and reverted to the parental phenotype at high frequency. One designated GRI 2677-8, was additionally auxotrophic and was further characterized. On the basis of these criteria the variants were assigned to one of 21 sub-groups. These results are discussed in relation to resistant clinical isolates and a possible mechanism that explains the diversity of variants.

UI	MeSH Term	Description	Entries
D008826	Microbial Sensitivity Tests	Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).	Bacterial Sensitivity Tests,Drug Sensitivity Assay, Microbial,Minimum Inhibitory Concentration,Antibacterial Susceptibility Breakpoint Determination,Antibiogram,Antimicrobial Susceptibility Breakpoint Determination,Bacterial Sensitivity Test,Breakpoint Determination, Antibacterial Susceptibility,Breakpoint Determination, Antimicrobial Susceptibility,Fungal Drug Sensitivity Tests,Fungus Drug Sensitivity Tests,Sensitivity Test, Bacterial,Sensitivity Tests, Bacterial,Test, Bacterial Sensitivity,Tests, Bacterial Sensitivity,Viral Drug Sensitivity Tests,Virus Drug Sensitivity Tests,Antibiograms,Concentration, Minimum Inhibitory,Concentrations, Minimum Inhibitory,Inhibitory Concentration, Minimum,Inhibitory Concentrations, Minimum,Microbial Sensitivity Test,Minimum Inhibitory Concentrations,Sensitivity Test, Microbial,Sensitivity Tests, Microbial,Test, Microbial Sensitivity,Tests, Microbial Sensitivity
D010403	Penicillin Resistance	Nonsusceptibility of an organism to the action of penicillins.	Penicillin Resistances,Resistance, Penicillin,Resistances, Penicillin
D010858	Pigmentation	Coloration or discoloration of a part by a pigment.	Pigmentations
D011995	Recombination, Genetic	Production of new arrangements of DNA by various mechanisms such as assortment and segregation, CROSSING OVER; GENE CONVERSION; GENETIC TRANSFORMATION; GENETIC CONJUGATION; GENETIC TRANSDUCTION; or mixed infection of viruses.	Genetic Recombination,Recombination,Genetic Recombinations,Recombinations,Recombinations, Genetic
D002228	Carbenicillin	Broad-spectrum semisynthetic penicillin derivative used parenterally. It is susceptible to gastric juice and penicillinase and may damage platelet function.	Carboxybenzyl Penicillin,Anabactyl,Carbapen,Carbecin,Carbenicillin Disodium,Geopen,Microcillin,Pyopen,Disodium, Carbenicillin,Penicillin, Carboxybenzyl
D000617	Aminoglycosides	Glycosylated compounds in which there is an amino substituent on the glycoside. Some of them are clinically important ANTIBIOTICS.	Aminoglycoside
D001618	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.	beta-Lactamase,beta Lactamase,beta Lactamases
D012706	Serratia marcescens	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria found in soil, water, food, and clinical specimens. It is a prominent opportunistic pathogen for hospitalized patients.