Cazemier A E, Verdoes J C, Op den Camp H J, Hackstein J H, van Ooyen A J
Department of Microbiology and Evolutionary Biology, Faculty of Science, University of Nijmegen, The Netherlands.
Appl Microbiol Biotechnol. 1999 Aug;52(2):232-9. doi: 10.1007/s002530051514.
A gene library of Cellulomonas pachnodae was constructed in Escherichia coli and was screened for endoglucanase activity. Five endoglucanase-positive clones were isolated that carried identical DNA fragments. The gene, designated cel6A, encoding an endoglucanase enzyme, belongs to the glycosyl hydrolase family 6 (cellulase family B). The recombinant Cel6A had a molecular mass of 53 kDa, a pH optimum of 5.5, and a temperature optimum of 50-55 degrees C. The recombinant endoglucanase Cel6A bound to crystalline cellulose and beech litter. Based on amino acid sequence similarity, a clear cellulose-binding domain was not distinguished. However, the regions in the Cel6A amino acid sequence at the positions 262-319 and 448-473, which did not show similarity to any of the known family-6 glycosyl hydrolases, may be involved in substrate binding.
构建了嗜木纤维单胞菌在大肠杆菌中的基因文库，并筛选内切葡聚糖酶活性。分离出五个携带相同DNA片段的内切葡聚糖酶阳性克隆。编码内切葡聚糖酶的基因命名为cel6A，属于糖基水解酶家族6（纤维素酶家族B）。重组Cel6A的分子量为53 kDa，最适pH为5.5，最适温度为50 - 55℃。重组内切葡聚糖酶Cel6A与结晶纤维素和山毛榉枯枝落叶结合。基于氨基酸序列相似性，未区分出明显的纤维素结合结构域。然而，Cel6A氨基酸序列中位置262 - 319和448 - 473的区域，与任何已知的6家族糖基水解酶均无相似性，可能参与底物结合。
