The importance of the negative charge of p-lactam compounds for the inactivation of the active-site serine DD-peptidase of Streptomyces
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چکیده
The interaction between the Streptomyces R61 penicillin-sensitive DD-peptidase and deacetyl-cephalosporin C or its lactone derivative has been studied at different pH values. The results show the importance of an enzyme group of pK g 9 which might form an ion pair with the free carboxylate of the former compound. This electrostatic interaction is shown to contribute to the formation of the first, non-covalent enzyme-inactivator complex by a factor of at least 50.
منابع مشابه
The importance of the negative charge of f - lactam compounds in the interactions with active - site serine DD - peptidases and fI - lactamases
The interaction between various penicillins and cephalosporins the carboxylate group of which at C-3 or C-4 had been esterified or amidated and different penicillin-recognizing enzymes was studied. In general, our findings reinforced the common assumption that an anionic group at that position is necessary for the effective acylation of these enzymes. However, the relative activities of the mod...
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تاریخ انتشار 2001