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：1975
卷号：72
期号：9
页码：3463-3467
DOI：10.1073/pnas.72.9.3463
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：D-Alanine carboxypeptidase from Bacillus stearothermophilus is a membrane-bound enzyme which is inhibited by covalent interaction with penicillin G. The penicilloyl enzyme spontaneously reactivates and simultaneously releases a penicillin G degradation product; 0.2 mumol of the latter was isolated after incubation of 4.2 mumol of [8-14C]penicillin G with 10 g of membrane protein. It was identified as phenylacetylglycine by chromatographic techniques, infrared spectroscopy, and mass spectrometry. A mechanism for the degradation is proposed in which the remaining part of penicillin G would be released as 5,5-dimethyl-delta2-thiazoline-4-carboxylic acid. The implications of this finding are discussed.
