Open AccessThe Primary Structure of Bovine Pancreatic Phospholipase A 2
Author(s) -
FLEER Eduard A. M.,
VERHEIJ Hubertus M.,
HAAS Gerard H.
Publication year - 1978
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1978.tb12019.x
Subject(s) - cyanogen bromide , edman degradation , trypsin , chymotrypsin , protein primary structure , chemistry , biochemistry , amino acid , peptide sequence , phospholipase , protease , phospholipase a , phospholipase a2 , enzyme , gene
The complete amino acid sequence of bovine phospholipase A 2 (EC 3.1.1.4) was determined. This enzyme has a molecular weight of 13 782 and consists of a single polypeptide chain of 123 amino acids cross‐linked by seven disulfide bridges. The main fragmentation of the polypeptide chain was accomplished by digesting the reduced and thialaminated derivative of the protein with trypsin, staphylococcal protease and cyanogen bromide. A number of chymotryptic peptides were used for alignment and to obtain overlaps of at least two residues. The sequence of the peptides was determined by Edman degradation by means of direct phenylthiohydantoin identification in combination with identification as dansyl amino acids. Although 71% of all residues of phospholipase A 2 from bovine, porcine and equine sources are conserved, bovine phospholipase A 2 differs from the others by the total number of residues and by substitutions at 20 (porcine) and 33 (equine) positions.