title: Crystallization and preliminary crystallographic data of the alpha-amylase inhibitors, Haim I and Paim I.
abstract: Two proteins that act as alpha-amylase inhibitors, Haim I and Paim I, were crystallized and preliminary X-ray diffraction studies on them were carried out. We also sequenced Haim I prepared from Streptomyces griseosporeus YM-25 and confirmed that it is composed of 78 amino acid residues. Crystals of Haim I were grown from ammonium sulfate solution mixed with ethanol by the vapor diffusion technique. The crystals grew as hexagonal bipyramids and diffracted X-rays beyond 2.0 A resolution. They belong to the space group P6(1)22 (or P6(5)22) with unit cell dimensions of a = b = 36.7 A, c = 192.4 A, and contain one molecule per asymmetric unit. Paim I, a protein of 39 amino acid residues produced by Streptomyces corchorusii, was crystallized under similar conditions to Haim I. The crystals diffracted X-rays beyond 2.5 A. They belong to the space group P4(1)2(1)2 (or P4(3)2(1)2) with unit cell dimensions of a = b = 65.4 A, c = 96.1 A, and contain three molecules per asymmetric unit.
authors.affiliation: Protein Engineering Research Institute, Osaka.
authors.forename: M
authors.initials: M
authors.lastname: Miyagawa
authors.forename: K
authors.initials: K
authors.lastname: Fukuhara
authors.forename: K
authors.initials: K
authors.lastname: Katayanagi
authors.forename: K
authors.initials: K
authors.lastname: Ishimaru
authors.forename: K
authors.initials: K
authors.lastname: Morikawa
authors.forename: T
authors.initials: T
authors.lastname: Matsuzaki
authors.forename: Y
authors.initials: Y
authors.lastname: Sato
authors.forename: S
authors.initials: S
authors.lastname: Hara
authors.forename: T
authors.initials: T
authors.lastname: Ikenaka
authors.forename: M
authors.initials: M
authors.lastname: Arai
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry*; D003460:Crystallization; D018360:Crystallography, X-Ray; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry*; D013302:Streptomyces / Q000737:chemistry; D000516:alpha-Amylases / Q000037:antagonists & inhibitors*
chemical_list: D001426:Bacterial Proteins; C087320:HAIM I protein, Streptomyces griseosporeus; D010455:Peptides; C054616:Paim I; D000516:alpha-Amylases