Biomaterial Database

Phenotypic suppression of methicillin resistance in Staphylococcus aureus by mutant noninducible penicillinase plasmids. 1972

S Cohen, and C J Gibson, and H M Sweeney

Methicillin (intrinsic) resistance of Staphylococcus aureus was suppressed almost completely by regulatory gene (penI(1)) mutations of penicillinase plasmids that made penicillinase production strictly noninducible. Methicillin resistance was restored by secondary regulatory gene mutations that altered the noninducible phenotype or by complementation with a compatible plasmid that did not bear the noninducible mutation. No evidence was obtained for genetic linkage between a penicillinase plasmid and the gene for methicillin resistance. We suggest, therefore, that the mutant noninducible repressor acted in trans by binding to a site on the methicillin resistance determinant. This hypothesis would imply an appreciable degree of homology between penicillinase plasmids and methicillin resistance genes.

UI	MeSH Term	Description	Entries
D008712	Methicillin	One of the PENICILLINS which is resistant to PENICILLINASE but susceptible to a penicillin-binding protein. It is inactivated by gastric acid so administered by injection.	Penicillin, Dimethoxyphenyl,Methicillin Hydrate, Monosodium Salt,Methicillin Monohydrate, Monosodium Salt,Methicillin Sodium,Meticillin,Metin,Staphcillin,Dimethoxyphenyl Penicillin
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
D009153	Mutagens	Chemical agents that increase the rate of genetic mutation by interfering with the function of nucleic acids. A clastogen is a specific mutagen that causes breaks in chromosomes.	Clastogen,Clastogens,Genotoxin,Genotoxins,Mutagen
D009154	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.	Mutations
D010403	Penicillin Resistance	Nonsusceptibility of an organism to the action of penicillins.	Penicillin Resistances,Resistance, Penicillin,Resistances, Penicillin
D010405	Penicillinase	A beta-lactamase preferentially cleaving penicillins. (Dorland, 28th ed) EC 3.5.2.-.	beta-Lactamase I,AER-I beta-Lactamase,Benzylpenicillinase,Carbenicillinase,Exopenicillinase,beta Lactamase III,beta Lactamase RP4,gamma-Penicillinase,AER I beta Lactamase,Lactamase RP4, beta,beta Lactamase I,beta-Lactamase, AER-I,gamma Penicillinase
D010641	Phenotype	The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.	Phenotypes
D002104	Cadmium	An element with atomic symbol Cd, atomic number 48, and atomic weight 112.41. It is a metal and ingestion will lead to CADMIUM POISONING.
D004790	Enzyme Induction	An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.	Induction, Enzyme
D005111	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.	Cytoplasmic Inheritance,Extranuclear Inheritance,Inheritance, Cytoplasmic,Inheritance, Extrachromosomal,Inheritance, Extranuclear