Characterization of conformers of D 1 of photosystem II using site-directed antibodies.
Antibodies have been raised to synthetic peptides, corresponding to a region in the loop spanning helices 4 and 5 of D 1 protein (Ala 250-Phe 265) and to a region anticipated to be near the C terminus of mature D 1 (His 332-Ala 345). Polyclonal antibodies to the sequence His 332-Ala 345 reacted with a 32 kDa polypeptide in thylakoid preparations identified as D 1 from its resistance (pea) or susceptibility (wheat) to lysine-C degradation. A monoclonal antibody to His 332-Ala 345 reacted preferentially with a faster migrating polypeptide in SDS electrophoresis, a putative conformer of D 1. Polyclonal antibodies to the sequence Ala 250-Phe 265 also reacted with the faster running polypeptide but not with the population of molecules running at 32 kDa. The putative conformer of D 1 from wheat appears to be more resistant than the main D 1 population to lysine-C degradation. Peptide analyses by Takahashi et al. [(1988) FEBS Lett, 240, 6-8] suggest Asn 335-Ala 344 lies at the processed C terminus. The present report provides immunological confirmation that this sequence is retained in mature D 1.
AFRC Institute of Horticultural Research, Littlehampton, West Sussex, U.K.
R T
RT
Besford
B
B
Thomas
N S
NS
Huskisson
G W
GW
Butcher
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies; D000911:Antibodies, Monoclonal; D002734:Chlorophyll / Q000276:immunology*; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes / Q000032:analysis; D045342:Light-Harvesting Protein Complexes; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010449:Peptide Mapping; D010455:Peptides / Q000138:chemical synthesis; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D010940:Plant Proteins / Q000276:immunology*; D010944:Plants / Q000378:metabolism; D051381:Rats / Q000276:immunology
D000906:Antibodies; D000911:Antibodies, Monoclonal; D000939:Epitopes; D045342:Light-Harvesting Protein Complexes; D010455:Peptides; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D002734:Chlorophyll