The orientation of halorhodopsin in the cell membrane of halobacteria.
The orientation of the light-driven chloride pump, halorhodopsin, in the membrane was determined using antibodies directed against a synthetic peptide which represents the C-terminal segment of the protein. Antibodies against this decapeptide did not bind to right-side-out cell vesicles. Partial inversion by sonication or lysis under low salt conditions exposed this COOH-terminal antigenic site. Antibody binding was removed by preincubation with the decapeptide. The COOH terminus of the molecule is therefore located on the cytoplasmic surface of the membrane.
Amino Acid Sequence↗