酸性β-半乳糖苷酶的晶体结构来自米曲霉。

The crystal structure of acidic β-galactosidase from Aspergillus oryzae.

机构信息

Department of Chemistry, University of Eastern Finland, P.O. Box 111, 80100 Joensuu, Finland.

出版信息

Int J Biol Macromol. 2013 Sep;60:109-15. doi: 10.1016/j.ijbiomac.2013.05.003. Epub 2013 May 17.

DOI:10.1016/j.ijbiomac.2013.05.003

Abstract

The crystal structure of the industrially important Aspergillus oryzae β-galactosidase has been determined at 2.60 Å resolution. The Ao-β-gal is a large (985 residues) monomeric multi-domain enzyme that has a catalytic (α/β)8-barrel domain. An electron density map revealed extensive N-glycosylation between the domain interfaces suggesting that the oligosaccharide-chains would have a stabilizing role for the structure of Ao-β-gal. Comparison of structure with other β-galactosidase structures of glycoside hydrolase family 35 revealed a number of hydrophobic residues, which may contribute favorably to the stabilization of the structure. The role of a high number of acidic residues in Ao-β-gal is also discussed.

摘要

已确定工业上重要的米曲霉β-半乳糖苷酶的晶体结构，分辨率为 2.60 Å。Ao-β-半乳糖苷酶是一种大型（985 个残基）单体多结构域酶，具有催化（α/β）8-桶结构域。电子密度图显示结构域界面之间存在广泛的 N-糖基化，表明寡糖链对 Ao-β-半乳糖苷酶的结构具有稳定作用。与糖苷水解酶家族 35 的其他β-半乳糖苷酶结构的比较揭示了许多疏水性残基，这些残基可能有利于稳定结构。还讨论了 Ao-β-半乳糖苷酶中大量酸性残基的作用。