TFPACD, A NOVEL BIFUNCTIONAL REAGENT FOR REACTING WITH DCCD SITES IN PROTEINS - STUDIES USING ESCHERICHIA-COLI ATP SYNTHASE

A novel cross-linker, trafluorobenzamido)hexyl]-3-cyclohexylcarbodiimi de (TFPACD), has been synthesized and tested by reaction with the Esch erichia coli ATP Synthase (ECF(1)F(0)). The reagent has a carbodiimide as one reactive group, which is shown to read with ECF(1)F(0) in a si milar way to 1,3-dicyclohexylcarbodiimide (DCCD) and modify the beta s ubunit of the ECF(1) part and the c subunit of the F-0 part. Reaction with both the ECF(1) and F-0 parts of the complex inhibited ATPase act ivity. The second reactive group in the reagent is the photoactivatabl e tetrafluorophenylazide moiety. Subsequent UV photolysis of TFPACD - modified ECF(1) and ECF(1)F(0) led to generation of cross-linked produ cts in significant yields, one between beta and alpha subunits; the se cond, dimers of the c subunit of the F-0 part. (C) 1994 Academic Press , Inc.