Nucleotide sequence of a multiple-copy gene for the B protein of photosystem II of a cyanobacterium

摘要: Abstract Chloroplast photogene 32 codes for the 32-kilodalton triazine herbicide-binding protein at B site of electron transport in photosystem II photosynthetic apparatus—its product is and gene accordingly designated ps2B here. The cyanobacteria Anacystis nidulans R2, Fremyella diplosiphon, Nostoc sp. MAC each contain several copies ps2B. sequence one copy from Fremyella, ps2B-1, has been determined. longest open reading frame would code a 360 amino acids. Although deduced acid ps2B-1 highly homologous overall to that corresponding spinach [Zurawski, G., Bohnert, H. J., Whitfeld, P. R. & Bottomley, W. (1982) Proc. Natl. Acad. Sci. USA 79, 7699-7703] and, excluding neutral substitutions, homology 95% an internal segment 309 acids, there are number nonneutral substitutions. Most differences net charge polarity occur first 20 acids terminus composition carboxyl terminus. nucleotide sequences 76% overall. Conserved resembling prokaryotic “-10” “-35” regions found remarkably similar positions F. diplosiphon although surrounding show only occasional homologies.