STABILITY AND FUNCTIONALITY OF CYSTEINE-LESS FOF1 ATP SYNTHASE FROM ESCHERICHIA-COLI

All 21 native cysteines in the Escherichia coli F0F1 ATP synthase were replaced by alanines, In isolated E. coli membranes, ATP-dependent pr oton pumping, turnover of ATP hydrolysis and steady-state transition s tate thermodynamic parameters of the cysteine-less enzyme were similar to wild-type. The cysteine-less enzyme was solubilized in n-octyl bet a-D-glucopyranoside, purified by affinity chromatography, and reconsti tuted into pre-formed liposomes made from E. coli lipids. The properti es of the reconstituted, purified enzyme mere not significantly differ ent from the membranous enzyme, These data demonstrate that cysteine-l ess F0F1 is biochemically stable and has functionality similar to wild -type. (C) 1998 Federation of European Biochemical Societies.