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

References listed in PDB file

Key reference

Title

Structure of bacillus halmapalus alpha-Amylase crystallized with and without the substrate analogue acarbose and maltose.

Authors

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

Ref.

Acta Crystallogr Sect F Struct Biol Cryst Commun, 2006, 62, 849-854. [DOI no: 10.1107/S174430910603096X]

PubMed id

16946462

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.

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.