Correlation of some published amino acid sequences for photosystem I polypeptides to a 17 kDa LHCI pigment-protein and to subunits III and IV of the core complex.
Photosystem I (PSI) in barley consists of at least 11 polypeptides of which three have apparent sizes of 15-19 kDa. Two of these polypeptides (subunits III and IV) are constituents of the core complex (CCI), the third is a component of the light-harvesting complex (LHCI). After fractionation of PSI into its CCI and LHCI components, each of the polypeptides has been isolated and its N-terminal region sequenced. We conclude that the gene sequence published for subunit IV of spinach [(1988) FEBS Lett. 237, 108-112] is not that of subunit IV but rather that of the 17 kDA LHCIc pigment protein. We confirm that the published sequence for subunit III [(1988) Curr. Genet. 14, 511-518] is indeed that of subunit III; seemingly conflicting identifications, based on apparent sizes on SDS-PAGE, of which polypeptides are subunits III and IV are probably explained by subunit III's electrophoretic migration rate being dependent on the solvent.
Anandan
S
S
Department of Biology, University of California, Los Angeles 90024-1606.
Vainstein
A
A
Thornber
J P
JP
D000595:Amino Acid Sequence; D001483:Base Sequence; D002734:Chlorophyll / Q000032:analysis*; D004591:Electrophoresis, Polyacrylamide Gel; D001467:Hordeum / Q000032:analysis; D008027:Light; D045342:Light-Harvesting Protein Complexes; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000032:analysis*; D045322:Photosynthetic Reaction Center Complex Proteins; D045331:Photosystem I Protein Complex; D010940:Plant Proteins / Q000032:analysis*; D010945:Plants, Edible / Q000032:analysis*; D011489:Protein Denaturation
D045342:Light-Harvesting Protein Complexes; D010446:Peptide Fragments; D045322:Photosynthetic Reaction Center Complex Proteins; D045331:Photosystem I Protein Complex; D010940:Plant Proteins; D002734:Chlorophyll