Open AccessPigment‐Protein Complexes from the Photosynthetic Membrane of the Cyanobacterium Synechocystis sp. PCC 6803
Author(s) -
Barbato Roberto,
Laureto Patrizia Polverino,
Rigoni Fernanda,
Martini Elena,
Giacometti Giorgio M.
Publication year - 1995
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1995.459_b.x
Subject(s) - synechocystis , photosynthesis , pigment , chemistry , cyanobacteria , biophysics , membrane , botany , biochemistry , biology , bacteria , gene , organic chemistry , mutant , genetics
Photosystem I and II core complexes were resolved in a single step from the thylakoid membrane of Synechocystis sp. PCC 6803 by using a mild solubilization procedure in dodecyl β‐ d ‐maltoside and Deriphat/PAGE. For each photosystem, two green bands were obtained containing oligomeric and monomeric forms of the core complexes of either photosystem. The oligomers are likely to be trimers in the case of photosystem I and dimers for photosystem II. The absorption spectra, polypeptide and pigment composition of green bands corresponding to either photosystem I or photosystem II were identical for monomeric and oligomeric forms. The cytochrome b ‐559 content of photosystem II was evaluated to be one cytochrome b ‐559/reaction centre both in the monomeric and dimeric forms. Two new 15‐kDa and 22‐kDa carotenoid‐binding proteins were isolated and their polypeptides purified to homogeneity.