The release of a 10‐kDa polypeptide from everted photosystem II thylakoid membranes by alkaline tris

Abstract

The release of polypeptides from inside‐out thylakoid vesicles and photosystem II by alkaline Tris treatment was reinvestigated, using SDS‐polyacrylanude gel electrophoresis (PAGE) in the presence of urea, with highly increased resolution in the low molecular mass region. In addition to the 33‐, 23‐, and 16‐kDa proteins of the oxygen‐evolving complex, a 10‐kDa polypeptide was released. This 10‐kDa polypeptide is an entrinsic polypeptide located at the inner grana thylakoid surface and with a likely role in photosynthetic oxygen evolution.