Three-dimensional structure of an alpha-amylase inhibitor HAIM as determined by nuclear magnetic resonance methods

• Published in: Journal of biochemistry (Tokyo) Vol. 108; no. 2; p. 158
• Main Authors: Yoshida, M, Nakai, T, Fukuhara, K, Saitoh, S, Yoshikawa, W, Kobayashi, Y, Nakamura, H
• Format: Journal Article
• Language: English
• Published: England 01-08-1990
• Subjects: alpha-Amylases - antagonists & inhibitors; Amino Acid Sequence; Bacterial Proteins - chemistry; Hydrogen-Ion Concentration; Magnetic Resonance Spectroscopy; Models, Chemical; Molecular Sequence Data; Peptides - chemistry; Protein Conformation; Streptomyces - analysis
• ISSN: 0021-924X
• DOI: 10.1093/oxfordjournals.jbchem.a123175

The three-dimensional structure of an alpha-amylase inhibitor, HAIM, composed of 78 amino acids, was analyzed by two-dimensional NMR techniques. Sequence-specific assignments were made for the amino acid residues from Ile-6 to Cys-72. Distance geometry analysis of the interresidue NOEs revealed that the HAIM molecule consists of two beta-sheets, as is the case in a homologous alpha-amylase inhibitor, Tendamistat, though one of its beta-strands is much shorter than that of Tendamistat. The combination of molecular modeling from Tendamistat and distance geometry analysis was confirmed to be useful for our purpose.