期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1981
卷号：78
期号：6
页码：3511-3515
DOI：10.1073/pnas.78.6.3511
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Membrane penicillinase (penicillin amido-beta-lactamhydrolase, EC 3.5.2.6 ) from Bacillus licheniformis bears a striking resemblance to the major outer membrane lipoprotein of Escherichia coli. It can be specifically labeled in vivo with [3H]glycerol, [35S]cysteine, or [3H]palmitate but not by [32P]orthophosphate. The labeled residues are located at or near the NH2 terminus of the membrane penicillinase because they can be completely removed by trypsin which cleaves a hydrophobic peptide(s) from the NH2 terminus, thereby rendering the enzyme hydrophilic. The membrane penicillinase produced by the 749/C gene carried in E. coli on phage lambda is similar to the enzyme formed in strain 749/C itself. The peptide antibiotic globomycin, which prevents processing of the E. coli prolipoprotein, severely inhibited the attachment of [3H]palmitate or [3H]glycerol to the 749/C enzyme (either in B. licheniformis 749/C or in E. coli), blocked the accumulation of penicillinase in the plasma membrane, and enhanced the formation of exoenzyme. Under the same conditions, globomycin does not prevent the attachment of palmitate or glycerol to the E. coli prolipoprotein but inhibits processing of the modified precursor to the mature lipoprotein. These results are in contrast with the lack of effect of globomycin on the RTEM-beta-lactamase of E. coli which has no detectable hydrophobic membrane form and was not labeled with palmitate or glycerol.
