title: 1H assignments and secondary structure determination of the soybean trypsin/chymotrypsin Bowman-Birk inhibitor.
abstract: The 1H resonance assignments and secondary structure of the trypsin/chymotrypsin Bowman-Birk inhibitor from soybeans were determined by nuclear magnetic resonance spectroscopy (NMR) at 600 MHz in an 18% acetonitrile-d3/aqueous cosolvent. Resonances from 69 of 71 amino acids were assigned sequence specifically. Residues Q11-T15 form an antiparallel beta-sheet with residues Q21-S25 in the tryptic inhibitory domain and an analogous region of antiparallel sheet forms between residues S38-A42 and Q48-V52 in the chymotryptic inhibitory domain. The inhibitory sites of each fragment (K16-S17 for trypsin, L43-S44 for chymotrypsin) are each part of a type VI like turn at one end of their respective region of the antiparallel beta-sheet. These structural elements are compared to those found in other Bowman-Birk inhibitors.
authors.affiliation: Chemical Biodynamics Division, Lawrence Berkeley Laboratory, University of California, Berkeley 94720.
authors.forename: M H
authors.initials: MH
authors.lastname: Werner
authors.forename: D E
authors.initials: DE
authors.lastname: Wemmer
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D002918:Chymotrypsin / Q000737:chemistry; D006859:Hydrogen; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D011487:Protein Conformation; D014357:Trypsin / Q000737:chemistry; D014358:Trypsin Inhibitor, Bowman-Birk Soybean / Q000737:chemistry*
chemical_list: D014358:Trypsin Inhibitor, Bowman-Birk Soybean; D006859:Hydrogen; D002918:Chymotrypsin; D014357:Trypsin