title: Location of the disulfide bonds in human plasma prekallikrein: the presence of four novel apple domains in the amino-terminal portion of the molecule.
abstract: The location of 16 of the 18 disulfide bonds in human plasma prekallikrein was determined by amino acid sequence analysis of cystinyl peptides produced by chemical and enzymatic digestions. A unique structure, named the apple domain, was established for each of the four tandem repeats in the amino-terminal portion of the molecule. The apple domains (90 or 91 amino acids) contain 3 highly conserved disulfide bonds linking the first and sixth, second and fifth, and third and fourth half-cystine residues present in each repeat. The fourth tandem repeat contains an extra disulfide bond that forms a second small loop within the apple domain. The carboxyl-terminal portion of plasma prekallikrein containing the catalytic region of the molecule was found to have disulfide bonds located in positions similar to those of other serine proteases.
authors.affiliation: Department of Biochemistry, University of Washington, Seattle 98195.
authors.forename: B A
authors.initials: BA
authors.lastname: McMullen
authors.forename: K
authors.initials: K
authors.lastname: Fujikawa
authors.forename: E W
authors.initials: EW
authors.lastname: Davie
mesh_terms: D000595:Amino Acid Sequence; D002851:Chromatography, High Pressure Liquid; D003488:Cyanogen Bromide; D004220:Disulfides / Q000032:analysis; D006801:Humans; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000302:isolation & purification; D011288:Prekallikrein / Q000302:isolation & purification; D011487:Protein Conformation; D014357:Trypsin
chemical_list: D004220:Disulfides; D010446:Peptide Fragments; D011288:Prekallikrein; D014357:Trypsin; D003488:Cyanogen Bromide