Nijikken Yuri, Tsukada Takeshi, Igarashi Kiyohiko, Samejima Masahiro, Wakagi Takayoshi, Shoun Hirofumi, Fushinobu Shinya
Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Tokyo 113-8657, Japan.
FEBS Lett. 2007 Apr 3;581(7):1514-20. doi: 10.1016/j.febslet.2007.03.009. Epub 2007 Mar 13.
The white-rot fungus Phanerochaete chrysosporium has two intracellular beta-glucosidases (BGL1A and BGL1B) belonging to glycoside hydrolase (GH) family 1. BGL1B effectively hydrolyzes cellobiose and cellobionolactone, but BGL1A does not. We have determined the crystal structure of BGL1A in substrate-free and gluconolactone complexed forms. The overall structure and the characteristic of subsite -1 (glycone site) were similar to those of other known GH1 enzymes. The loop regions covering on the (beta/alpha)(8) barrel was significantly deviated, and they form a unique subsite +1 (aglycone site) of BGL1A.
白腐真菌黄孢原毛平革菌有两种属于糖苷水解酶(GH)家族1的细胞内β-葡萄糖苷酶(BGL1A和BGL1B)。BGL1B能有效水解纤维二糖和纤维二糖内酯,但BGL1A不能。我们已经确定了无底物形式和与葡糖酸内酯复合形式的BGL1A的晶体结构。其整体结构以及亚位点-1(糖基位点)的特征与其他已知的GH1酶相似。覆盖在(β/α)8桶状结构上的环区域有显著偏差,它们形成了BGL1A独特的亚位点+1(苷元位点)。