Amino acid sequence of the 8-kDa protein in photosystem I reaction center complex from a thermophilic cyanobacterium, Synechococcus elongatus.
The 8-kDa protein in Photosystem I (PS I) reaction center complex was isolated from a thermophilic cyanobacterium, Synechococcus elongatus, by SDS-polyacrylamide gel electrophoresis using TRIS-Tricine buffer system. The complete amino acid sequence of the protein was determined. The 8-kDa protein consisted of 73 amino acid residues giving a calculated molecular weight of 7,472. No significant sequence homology were observed with the known other small subunits in PS I reaction center complex, except for the 6.5-kDa protein in PS I from another thermophilic cyanobacterium, S. vulcanus. The 8-kDa protein was characteristically rich in hydrophobic amino acid residues, especially the content of leucine. These suggest that the 8-kDa subunit is an intrinsic structure component in PS I core complex for stabilization of the reaction center.
Jone
C S
CS
Research Institute for Biosciences, Science University of Tokyo, Japan.
Kotani
N
N
Aso
K
K
Yang
L
L
Enami
I
I
Kondo
K
K
Tsugita
A
A
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000458:Cyanobacteria / Q000737:chemistry*; D008969:Molecular Sequence Data; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry*; D045331:Photosystem I Protein Complex; D016415:Sequence Alignment
D000596:Amino Acids; D045322:Photosynthetic Reaction Center Complex Proteins; D045331:Photosystem I Protein Complex