2 SUBUNITS OF THE F0F1-ATPASE ARE PHOSPHORYLATED IN THE INNER MITOCHONDRIAL-MEMBRANE

Inside out submitochondrial particles from potato tuber mitochondria w ere incubated with [gamma-P-32]ATP, More than 16 phosphorylated polype ptides were detected by autoradiography on an SDS-gel, Two phosphoprot eins, migrating at 22 and 28 kDa, were excised from the SDS-gel, elect roeluted, and purified further by anion chromatography, The phosphopro teins were N-terminally sequenced, Over the regions sequenced, the 22 and 28 kDa phosphoproteins had 100% sequence identity with potato prot eins identified as the delta'-subunit of the F-1-ATPase and the b-subu nit of the F-o-ATPase, respectively, We suggest that phosphorylation o f these proteins may control the interaction between F-1 and F-o and r egulate energy coupling in oxidative phosphorylation. (C) 1998 Academi c Press.