A novel method for the identification and distinction of the beta-lactamases of the genus Acinetobacter.
The characterization of the chromosomal beta-lactamases of Acinetobacter has proved difficult because of the poor focusing of these enzymes in conventional isoelectric focusing on polyacrylamide gels. We describe a novel isoelectric focusing method, which employs an agarose gel incorporating a detergent with sorbitol and urea, to examine the beta-lactamases produced by eight clinical strains of Acinetobacter calcoaceticus; we have identified four different beta-lactamases. The molecular masses of each of the beta-lactamases was estimated and most of them ranged from 600,000 to greater than 1,000,000. These are the largest beta-lactamases so far described and their size is likely to be one reason for their poor solubility in conventional polyacrylamide systems.
Hood
J
J
Department of Bacteriology, Medical School, University of Edinburgh, UK.
Amyes
S G
SG
D000150:Acinetobacter / Q000201:enzymology*; D004587:Electrophoresis, Agar Gel; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007525:Isoelectric Focusing; D008970:Molecular Weight; D001618:beta-Lactamases / Q000032:analysis*
D001618:beta-Lactamases