期刊论文

中文

湖南农业大学学报(自然科学版)

1007-1032

2011

37

1

22-25

10.3724/SP.J.1238.2011.00022

湖南省科学技术厅项目（01JZY2099）；

本校为第一机构

从湘西富含豆粕下脚料土壤中筛选鉴定出1株产α-半乳糖苷酶细菌,对其进行显微形态观察、分子生物学鉴定及酶学特性分析。结果表明,该细菌为球形细菌,革兰氏染色阳性,16S rDNA序列与乳球菌有98%的同源性,可以确定为乳球菌属。细菌产分泌性α-半乳糖苷酶,其胞外α-半乳糖苷酶摇瓶发酵液初酶活为6.21 U/mL,在45℃、pH 5.5时该酶活性表现为最大值。酶的表达受D-棉籽糖的诱导和葡萄糖的抑制,当D-棉籽糖的浓度为30μmol/mL时诱导效果最佳,当葡萄糖浓度为30μmol/mL时对该酶的合成有较明显的抑制作用,表现为糖代谢操纵元的典型调控方式。

A strain of α-galactosidase producing bacterium was screened out from the soil rich in soybean wastes of Western Hunan.The bacterium morphology observation,molecular biological identification and enzymatic characteristics was analysed.The bacterium was a stained gram positive and its 16S rDNA had homology with Lactoccus.It was identified as a strain bacterium of Lactoccus family.The bacteria produced an excretive α-galactosidase.The maximal α-galactosidase activity of shaking cultured supernatant was 6.21 U/mL.The α-galactosidase showed the...