Micrococcus lysodeikticus ATPase. Purification by preparative gel electrophoresis and subunit structure studied by urea and sodium dodecylsulfate gel electrophoresis

Abstract

Micrococcus lysodeikticus ATPase was purified by preparative gel electrophoresis after its "shodk wash" release from the membrane. The method afforded the highest yield of pure protein in the minimum time as compared with former purification procedures. The pure protein had a specific activity of 7 mumol Pi-min- minus 1-mg- minus 1 with incubation times not longer than 3 min, 345 000 mol. wt and was not stimulated by trypsin. By gel electrophoresis at alkaline pH (8.5) in 8 M urea or in sokium dodecylsulfate, the ATPase revealed a complex pattern with two major subunits (alpha and beta) and two minor ones (gamma and delta). The non-identity between the major subunits was demonstrated.