Broad spectrum beta-lactamases of Citrobacter diversus.
Citrobacter diversus NF85 produced a chromosomal beta-lactamase that was induced by a variety of beta-lactam antibiotics. Two major forms of the enzyme, with isoelectric points (pI's) of 5.7 and 6.2, were found in crude cell extracts. Derepressed mutants of NF85, generated by nitrosoguanidine treatment, displayed different levels of beta-lactamase expression to the parent strain and had different patterns of resistance to a range of beta-lactam antibiotics. Those mutants of NF85 that were totally derepressed, expressing high, constitutive levels of enzyme, were found to have an additional beta-lactamase activity with a pI of 6.8.
Oliva
B
B
Department of Biomedical Sciences, University of L'Aquila, Italy.
Segatore
B
B
Amicosante
G
G
Franceschini
N
N
Oratore
A
A
Bennett
P M
PM
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002954:Citrobacter / Q000187:drug effects / Q000201:enzymology*; D004790:Enzyme Induction / Q000187:drug effects; D007525:Isoelectric Focusing; D008826:Microbial Sensitivity Tests; D009154:Mutation; D001618:beta-Lactamases / Q000096:biosynthesis* / Q000378:metabolism; D047090:beta-Lactams
D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D001618:beta-Lactamases