PDBsum entry 2gjp

Hydrolase

PDB id: 2gjp

Contents

Protein chain

481 a.a. *

Ligands

BGC-GLC-DAF

GLC-GLC-GLC-DAF

GLC-GLC

GLC ×2

Metals

_NA

_CA ×3

Waters ×215

* Residue conservation analysis

PDB id:

2gjp

Name:

Hydrolase

Title:

Structure of bacillus halmapalus alpha-amylase, crystallized with the substrate analogue acarbose and maltose

Structure:

Alpha-amylase. Chain: a. Engineered: yes

Source:

Bacillus halmapalus. Organism_taxid: 79882. Expressed in: bacillus subtilis. Expression_system_taxid: 1423

Resolution:

1.90Å R-factor: 0.174 R-free: 0.214

Authors:

L.Lyhne-Iversen,T.J.Hobley,S.G.Kaasgaard,P.Harris

Key ref:

L.Lyhne-Iversen et al. (2006). Structure of Bacillus halmapalus alpha-amylase crystallized with and without the substrate analogue acarbose and maltose. Acta Crystallogr Sect F Struct Biol Cryst Commun, 62, 849-854. PubMed id: 16946462 DOI: 10.1107/S174430910603096X

Date:

31-Mar-06 Release date: 05-Sep-06

Protein chain

P19571  (AMT6_BACS7) -  Glucan 1,4-alpha-maltohexaosidase from Bacillus sp. (strain 707)

Seq: 518 a.a.

Struc: 481 a.a.*

* PDB and UniProt seqs differ at 68 residue positions (black crosses)

Enzyme reactions

• Enzyme class: E.C.3.2.1.98 - glucan 1,4-alpha-maltohexaosidase.
• Reaction: Hydrolysis of 1,4-alpha-D-glucosidic linkages in amylaceous polysaccharides so as to remove successive maltohexaose residues from the non-reducing chain ends.

DOI no: 10.1107/S174430910603096X

Acta Crystallogr Sect F Struct Biol Cryst Commun 62:849-854 (2006)

PubMed id: 16946462

Structure of Bacillus halmapalus alpha-amylase crystallized with and without the substrate analogue acarbose and maltose.

L.Lyhne-Iversen, T.J.Hobley, S.G.Kaasgaard, P.Harris.

ABSTRACT

Recombinant Bacillus halmapalus alpha-amylase (BHA) was studied in two different crystal forms. The first crystal form was obtained by crystallization of BHA at room temperature in the presence of acarbose and maltose; data were collected at cryogenic temperature to a resolution of 1.9 A. It was found that the crystal belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 47.0, b = 73.5, c = 151.1 A. A maltose molecule was observed and found to bind to BHA and previous reports of the binding of a nonasaccharide were confirmed. The second crystal form was obtained by pH-induced crystallization of BHA in a MES-HEPES-boric acid buffer (MHB buffer) at 303 K; the solubility of BHA in MHB has a retrograde temperature dependency and crystallization of BHA was only possible by raising the temperature to at least 298 K. Data were collected at cryogenic temperature to a resolution of 2.0 A. The crystal belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 38.6, b = 59.0, c = 209.8 A. The structure was solved using molecular replacement. The maltose-binding site is described and the two structures are compared. No significant changes were seen in the structure upon binding of the substrates.

Selected figure(s)

Figure 3.
The tertiary structure of B. halmapalus [alpha]-amylase in the complexed crystal form. The N-terminal ([beta]/[alpha])[8]-barrel domain is shown in blue, the loop domain in turquoise and the C-terminal [beta]-sheet domain in red. The nonasaccharide and maltose are shown as yellow sticks and the two glucose molecules are shown as green sticks. Metal ions are shown as spheres. The figure was produced using PyMOL (DeLano, 2002[triangle]). Acta Crystallogr Sect F Struct Biol Cryst Commun. 2006 September 1; 62(Pt 9): 849–854. Published online 2006 August 26. doi: 10.1107/S174430910603096X. Copyright [copyright] International Union of Crystallography 2006

Figure 5.
Maltose (red) shown in the complexed crystal structure (blue). The uncomplexed crystal form is superimposed (green). The illustration was produced using O (Jones et al., 1991[triangle]). Acta Crystallogr Sect F Struct Biol Cryst Commun. 2006 September 1; 62(Pt 9): 849–854. Published online 2006 August 26. doi: 10.1107/S174430910603096X. Copyright [copyright] International Union of Crystallography 2006

The above figures are reprinted from an Open Access publication published by the IUCr: Acta Crystallogr Sect F Struct Biol Cryst Commun (2006, 62, 849-854) copyright 2006.

Figures were selected by an automated process.