Unexpected influence of ionic strength on branched-pathway interactions between beta-lactamases and beta-halogenopenicillanates.

نویسندگان

  • F De Meester
  • A Matagne
  • G Dive
  • J M Frère
چکیده

Ionic strength strongly influenced the turnover/inactivation ratio in the interaction between beta-halogenopenicillanates and some class A beta-lactamases. This suggested the stabilization of a highly charged intermediate by solvation. Those data could be interpreted on the basis of a reaction pathway where an episulphonium ion was transiently formed. The various mechanisms proposed for explaining the formation of the dihydrothiazine chromophore are discussed.

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عنوان ژورنال:
  • The Biochemical journal

دوره 257 1  شماره 

صفحات  -

تاریخ انتشار 1989