Structure of a Bacillus halmapalus family 13 alpha-amylase, BHA, in complex with an acarbose-derived nonasaccharide at 2.1 A resolution.
نویسندگان
چکیده
The enzymatic digestion of starch by alpha-amylases is one of the key biotechnological reactions of recent times. In the search for industrial biocatalysts, the family GH13 alpha-amylase BHA from Bacillus halmapalus has been cloned and expressed. The three-dimensional structure at 2.1 A resolution has been determined in complex with the (pseudo)tetrasaccharide inhibitor acarbose. Acarbose is found bound as a nonasaccharide transglycosylation product spanning the -6 to +3 subsites. Careful inspection of electron density suggests that the bound ligand could not have been formed through successive transglycosylations of acarbose and must also have featured maltose or maltooligosaccharides as an acceptor.
منابع مشابه
Structure of Bacillus halmapalus α-amylase crystallized with and without the substrate analogue acarbose and maltose
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 ...
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ورودعنوان ژورنال:
- Acta crystallographica. Section D, Biological crystallography
دوره 61 Pt 2 شماره
صفحات -
تاریخ انتشار 2005