Studies on the structure of the photo-synthetic reaction centre of green thermophilic bacterium Chloroflexus aurantiacus
M. A. Kutuzov, B. E. Shmukler, A. A. Zargarov, I. N. Telezhinskaya, N. B. Levina, A. S. Zolotarev, N. G. Abdulaev
M. M. Shemyakin Institute of Bioorganic Chemistry, Academy of Sciences of the USSR, Moscow
Abstract: Analysis of the Chloroflexus aurantiacus reaction centre (RC) using both protein and recombinant DNA techniques resulted in determination of its polypeptide composition and the primary structures of its two subunits. A model of the polypeptide chains' folding in the membrane is suggested based on: i) homology between L- and M-subunits of Chloroflexus aurantiacus RC and their counterparts in purple bacteria; ii) comparison of their hydropathy plots, and iii) data on the tertiary structures of purple bacteria RCs. The role of a number of functionally important amino acid residues in the RC electron transport activity is discussed. Limited proteolysis of the RC under non-denaturing conditions was used to determine the contribution of the N-terminal regions to its thermal stability.
Russian Journal of Bioorganic Chemistry 1990, 16 (9):1218-1235