The structure of the AliC GH13 α-amylase from Alicyclobacillus sp. reveals the accommodation of starch branching points in the α-amylase family
| Autor: | Jon Agirre, Olga Moroz, Sebastian Meier, Jesper Brask, Astrid Munch, Tine Hoff, Carsten Andersen, Keith S. Wilson, Gideon J. Davies |
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| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
0303 health sciences
starch branching points Magnetic Resonance Spectroscopy Alicyclobacillus 030302 biochemistry & molecular biology Starch Research Papers Pullulan Substrate Specificity 03 medical and health sciences AliC GH13 α-analyse pullulan Structural Biology carbohydrate-active enzymes Glycoside hydrolases AliC GH13 α-amylase Carbohydrate-active enzymes glycoside hydrolases Glycoside Hydrolase Inhibitors Acarbose alpha-Amylases Starch brancing points 030304 developmental biology |
| Zdroj: | Agirre, J, Moroz, O V, Meier, S, Braak, J, Munch, A, Hoff, T, Anderson, C, Wilson, K S & Davies, G J 2019, ' Structure of the AliC GH13 α−amylase from Alicyclobacillus sp, reveals accommodation of starch branching points in the α−amylase family ', Acta crystallographica Section D: Structural biology, vol. 75, no. 1, pp. 1-7 . https://doi.org/10.1107/S2059798318014900 Acta Crystallographica. Section D, Structural Biology |
| ISSN: | 2059-7983 |
| DOI: | 10.1107/S2059798318014900 |
| Popis: | In the light of NMR data on product profiles, the structure of an Alicyclobacillus sp. CAZy family GH13 α-amylase highlights the accommodation of branch points in the α-amylase active centre. α-Amylases are glycoside hydrolases that break the α-1,4 bonds in starch and related glycans. The degradation of starch is rendered difficult by the presence of varying degrees of α-1,6 branch points and their possible accommodation within the active centre of α-amylase enzymes. Given the myriad industrial uses for starch and thus also for α-amylase-catalysed starch degradation and modification, there is considerable interest in how different α-amylases might accommodate these branches, thus impacting on the potential processing of highly branched post-hydrolysis remnants (known as limit dextrins) and societal applications. Here, it was sought to probe the branch-point accommodation of the Alicyclobacillus sp. CAZy family GH13 α-amylase AliC, prompted by the observation of a molecule of glucose in a position that may represent a branch point in an acarbose complex solved at 2.1 Å resolution. Limit digest analysis by two-dimensional NMR using both pullulan (a regular linear polysaccharide of α-1,4, α-1,4, α-1,6 repeating trisaccharides) and amylopectin starch showed how the Alicyclobacillus sp. enzyme could accept α-1,6 branches in at least the −2, +1 and +2 subsites, consistent with the three-dimensional structures with glucosyl moieties in the +1 and +2 subsites and the solvent-exposure of the −2 subsite 6-hydroxyl group. Together, the work provides a rare insight into branch-point acceptance in these industrial catalysts. |
| Databáze: | OpenAIRE |
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