The D1 and D2 proteins of dinoflagellates: unusually accumulated mutations which influence on PSII photoreaction.
Plastid encoded genes of the dinoflagellates are rapidly evolving and most divergent. The importance of unusually accumulated mutations on structure of PSII core protein and photosynthetic function was examined in the dinoflagellates, Symbiodinium sp. and Alexandrium tamarense. Full-length cDNA sequences of psbA (D1 protein) and psbD (D2 protein) were obtained and compared with the other oxygen-evolving photoautotrophs. Twenty-three amino acid positions (7%) for the D1 protein and 34 positions (10%) for the D2 were mutated in the dinoflagellates, although amino acid residues at these positions were conserved in cyanobacteria, the other algae, and plant. Many mutations were likely to distribute in the N-terminus and the D-E interhelical loop of the D1 protein and helix B of D2 protein, while the remaining regions were well conserved. The different structural properties in these mutated regions were supported by hydropathy profiles. The chlorophyll fluorescence kinetics of the dinoflagellates was compared with Synechocystis sp. PCC6803 in relation to the altered protein structure.
Kobe University Research Center for Inland Seas, Awaji, Hyogo 656-2401, Japan.
Satoko
S
Iida
Atsushi
A
Kobiyama
Takehiko
T
Ogata
Akio
A
Murakami
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D002734:Chlorophyll / Q000378:metabolism; D004252:DNA Mutational Analysis; D004141:Dinoflagellida / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D005453:Fluorescence; D007700:Kinetics; D008969:Molecular Sequence Data; D010788:Photosynthesis; D045332:Photosystem II Protein Complex / Q000737:chemistry* / Q000235:genetics; D017433:Protein Structure, Secondary; D016053:RNA, Protozoan / Q000235:genetics; D016415:Sequence Alignment; D046939:Synechocystis / Q000378:metabolism
D001426:Bacterial Proteins; D045332:Photosystem II Protein Complex; D016053:RNA, Protozoan; C422369:photosystem II, psbA subunit; C085993:psbDI protein, cyanobacteria; D002734:Chlorophyll