Crystal structure of alpha-amylase from Oryza sativa: molecular insights into enzyme activity and thermostabilityOchiai, A., Sugai, H., Harada, K., Tanaka, S., Ishiyama, Y., Ito, K., Tanaka, T., Uchiumi, T., Taniguchi, M., Mitsui, T.
(2014) Biosci Biotechnol Biochem 78: 989-997
- PubMed: 25036124
- DOI: https://doi.org/10.1080/09168451.2014.917261
- Primary Citation of Related Structures:
- PubMed Abstract:
AmyI-1 is an α-amylase from Oryza sativa (rice) and plays a crucial role in degrading starch in various tissues and at various growth stages. This enzyme is a glycoprotein with an N-glycosylated carbohydrate chain, a unique characteristic among plant α-amylases ...
AmyI-1 is an α-amylase from Oryza sativa (rice) and plays a crucial role in degrading starch in various tissues and at various growth stages. This enzyme is a glycoprotein with an N-glycosylated carbohydrate chain, a unique characteristic among plant α-amylases. In this study, we report the first crystal structure of AmyI-1 at 2.2-Å resolution. The structure consists of a typical (β/α)8-barrel, which is well-conserved among most α-amylases in the glycoside hydrolase family-13. Structural superimposition indicated small variations in the catalytic domain and carbohydrate-binding sites between AmyI-1 and barley α-amylases. By contrast, regions around the N-linked glycosylation sites displayed lower conservation of amino acid residues, including Asn-263, Asn-265, Thr-307, Asn-342, Pro-373, and Ala-374 in AmyI-1, which are not conserved in barley α-amylases, suggesting that these residues may contribute to the construction of the structure of glycosylated AmyI-1. These results increase the depths of our understanding of the biological functions of AmyI-1.
a Faculty of Engineering, Department of Materials Science and Technology , Niigata University , Niigata , Japan.