title: Amino acid sequences of trypsin-chymotrypsin inhibitors (A-I, A-II, B-I, and B-II) from peanut (Arachis hypogaea): a discussion on the molecular evolution of legume Bowman-Birk type inhibitors.
abstract: The amino acid sequences of four peanut protease inhibitors (A-I, A-II, B-I, and B-II) were determined by conventional methods and by comparison of peptide maps of their tryptic digests with that of B-III on HPLC. A-I, A-II, B-I, and B-III had the same amino acid sequence except for differences in their N-terminal regions. This suggests that the four inhibitors would be derived from an original inhibitor with a longer N-terminal amino acid sequence by proteolysis of its N-terminal region. But B-II possessed an extremely different amino acid sequence from those of the other peanut inhibitors and was thought to be biosynthesized from a gene different from that of the other inhibitors. A phylogenetic tree of legume double-headed inhibitors was constructed on the basis of the matrix of amino acid differences among their sequences. The double-headed inhibitors whose sequences have been determined were classified into four groups.
mesh_terms: D000595:Amino Acid Sequence; D010367:Arachis / Q000032:analysis*; D002918:Chymotrypsin / Q000037:antagonists & inhibitors*; D010940:Plant Proteins; D011487:Protein Conformation; D014361:Trypsin Inhibitors / Q000302:isolation & purification*
chemical_list: D010940:Plant Proteins; D014361:Trypsin Inhibitors; D002918:Chymotrypsin