PARTIAL AMINO-ACID SEQUENCE OF THE LARGE SUBUNIT OF RIBULOSEBISPHOSPHATE CARBOXYLASE FROM BARLEY

The large subunit of D-ribulose-1,5-bisphosphate carboxylase (E.C. 4.1.1.39) from barley has been subjected to partial amino acid sequencing. The amino-terminal sequence comprising 46 residues of the reduced and carboxymethylated large subunit polypeptide has been determined. The carboxy-terminal end contained the sequence-Leu-Ala-Val · COOH. Eight of the ten cyanogen bromide fragments have been partially sequenced from the N-terminus. A ninth fragment was found to be blocked to N-terminal sequencing due to cyclization of a glutamine residue after cyanogen bromide cleavage. The eight sequences which have been determined comprise 210 of the approximate 490 residues in the large subunit. The sequences have been compared to five sequences of the large subunit from spinach. Among 37 residues which could be compared four differences were encountered. © 1979 Carlsberg Laboratory.