Identification of an inducible penicillinase of the lithoautotrophic hydrogen-oxidizing bacterium Alcaligenes eutrophus.
The growth of Alcaligenes eutrophus in the presence of benzylpenicillin under heterotrophic and autotrophic conditions was studied. The drug induced a penicillinase in the cells, which can be readily released and extracted from the cells after a lysozyme and EDTA treatment in the course of spheroplast formation. The isoelectric point of the enzyme is 8.1 and the molar mass was estimated to be nearly 25 kg/mol. Phenoxypenicillin is hydrolyzed in the presence of the enzyme at a higher relative rate than benzylpenicillin, ampicillin, amoxycillin and azlocillin. The cephalosporins tested, i.e. cephalosporin C, cefalexin, cefotaxime and 7-aminocephalosporanic acid, were hydrolyzed at a substantially lower relative rate than the penicillins, indicating that the enzyme is a penicillinase.
D000421:Alcaligenes / Q000201:enzymology*; D004790:Enzyme Induction; D006859:Hydrogen / Q000378:metabolism*; D007525:Isoelectric Focusing; D007700:Kinetics; D008970:Molecular Weight; D010084:Oxidation-Reduction; D010405:Penicillinase / Q000096:biosynthesis* / Q000302:isolation & purification / Q000378:metabolism; D013379:Substrate Specificity
D006859:Hydrogen; D010405:Penicillinase