Crystallization of photosystem I complexes from the thermophilic cyanobacterium, Synechococcus vulcanus

Abstract

PSI complexes were isolated from the thermophilic cyanobacterium, Synechococcus vulcanus, by mild detergent treatment of the thylakoid membranes, purified by sucrose-density gradient centrifugation, and then crystallized. High resolution SDS-PAGE revealed the presence of the product of the psaI gene in S. vulcanus PSI complexes and crystals. Crystals of the PSI complexes retained all of the components of electron carriers and subunit polypeptides (including PsaX) known in cyanobacteria.