The complete amino acid sequence of a bacteriochlorophyll a-protein from Prosthecochloris aestuarii

The amino acid sequence of a bacteriochlorophyll a-protein from the green photosynthetic bacterium Prosthecochloris aestuarii strain 2K has been determined. Use was made of a tentative sequence deduced from a 2.8-A electron density map of the protein to help locate sequenced peptides. The polypeptide chain consists of 366 amino acids. The identities of 5 amino acids that ligand to the magnesium atoms of 5 of the 7 bacteriochlorophyll molecules present in each subunit of the trimeric complex have been confirmed as histidines.