Biomaterial Database

Polypeptide folding of Bacillus cereus ATCC7064 oligo-1,6-glucosidase revealed by 3.0 A resolution X-ray analysis. 1993

H Kizaki, and Y Hata, and K Watanabe, and Y Katsube, and Y Suzuki

Department of Agricultural Chemistry, Kyoto Prefectural University.

The crystal structure of an oligo-1,6-glucosidase from Bacillus cereus ATCC7064 was determined by the X-ray diffraction method at 3.0 A resolution. The structure was solved by the multiple isomorphous replacement method and refined to a crystallographic R-factor of 0.208, using the molecular dynamics refinement program, X-PLOR. The electron density map revealed the folding of a polypeptide chain consisting of 558 amino acid residues. The molecule can be subdivided into three domains (N-terminal domain, subdomain, and C-terminal domain). The N-terminal domain has an (alpha/beta)8-barrel structure called the TIM-barrel structure. The C-terminal domain is characterized by a beta-barrel structure composed of eight antiparallel beta-strands, while the subdomain has a loop-rich structure with a small alpha-helix and a beta-sheet. The enzyme has a large cleft between the N-terminal domain and the subdomain. The cleft leads from the molecular surface to the molecular center. The bottom of the cleft is at the C-terminal end of the parallel beta-strands of the (alpha/beta)8-barrel. These structural features closely resemble those of alpha-amylases from Aspergillus oryzae and pig pancreas.

UI	MeSH Term	Description	Entries
D009834	Oligo-1,6-Glucosidase	An enzyme that catalyzes the endohydrolysis of 1,6-alpha-glucosidic linkages in isomaltose and dextrins produced from starch and glycogen by ALPHA-AMYLASES. EC 3.2.1.10.	Isomaltase,Exo-Oligo-1,6-Glucosidase,Exo Oligo 1,6 Glucosidase,Oligo 1,6 Glucosidase
D001409	Bacillus cereus	A species of rod-shaped bacteria that is a common soil saprophyte. Its spores are widespread and multiplication has been observed chiefly in foods. Contamination may lead to food poisoning.
D014961	X-Ray Diffraction	The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Xray Diffraction,Diffraction, X-Ray,Diffraction, Xray,Diffractions, X-Ray,Diffractions, Xray,X Ray Diffraction,X-Ray Diffractions,Xray Diffractions
D015394	Molecular Structure	The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.	Structure, Molecular,Molecular Structures,Structures, Molecular
D017433	Protein Structure, Secondary	The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to ALPHA-HELICES; BETA-STRANDS (which align to form BETA-SHEETS), or other types of coils. This is the first folding level of protein conformation.	Secondary Protein Structure,Protein Structures, Secondary,Secondary Protein Structures,Structure, Secondary Protein,Structures, Secondary Protein
D017510	Protein Folding	Processes involved in the formation of TERTIARY PROTEIN STRUCTURE.	Protein Folding, Globular,Folding, Globular Protein,Folding, Protein,Foldings, Globular Protein,Foldings, Protein,Globular Protein Folding,Globular Protein Foldings,Protein Foldings,Protein Foldings, Globular