Correlation between hydrolysis of the -lactam bond of the cephalosporin nucleus and expulsion of the 3-substituent.
نویسندگان
چکیده
The hydrolysis of two cephalosporins by three different beta-lactamases has been studied. Each enzyme caused a decrease in ultraviolet absorption, a loss of biological activity, and the release of the leaving group from the 3-position. The changes occurred at the same rate and to the same extent with each enzyme, and it is inferred that the loss of the leaving group is a consequence of, and not a prerequisite for, hydrolysis of the beta-lactam ring.
منابع مشابه
بررسی آنزیم سفالوسپورین آسیلاز در برخی باکتری‌های گرم منفی جدا شده از نمونه‌های بالینی جهت تولید آنتی‌بیوتیک‌های نیمه سنتزی سفالوسپورینی در صنایع داروسازی
Background and Objective: Cephalosporin acylases (CA) are highly specialized peptidases that are able to break down the amide bond between the lactam nucleus and lateral chain without destruction of beta-lactam ring. This enzyme transmutes the cephalosporin C to 7-ACA. The 7-ACA is an important intermediate in synthesizing the semi-synthetic cephalosporin in pharmaceutical industries. The purpo...
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ورودعنوان ژورنال:
- Journal of bacteriology
دوره 110 3 شماره
صفحات -
تاریخ انتشار 1972