Gene cloning and expression of a new acidic family 7 endo-beta-1,3-1,4-glucanase from the acidophilic fungus Bispora sp. MEY-1.
Most reported microbial beta-1,3-1,4-glucanases belong to the glycoside hydrolase family 16. Here, we report a new acidic family 7 endo-beta-1,3-1,4-glucanase (Bgl7A) from the acidophilic fungus Bispora sp. MEY-1. The cDNA of Bgl7A was isolated and over-expressed in Pichia pastoris, with a yield of about 1,000 U ml(-1) in a 3.7-l fermentor. The purified recombinant Bgl7A had three activity peaks at pH 1.5, 3.5, and 5.0 (maximum), respectively, and a temperature optimum at 60 degrees C. The enzyme was stable at pH 1.0-8.0 and highly resistant to both pepsin and trypsin. Belonging to the group of non-specific endoglucanase, Bgl7A can hydrolyze not only beta-glucan and cellulose but also laminarin and oat spelt xylan. The specific activity of Bgl7A against barley beta-glucan and lichenan (4,040 and 2,740 U mg(-1)) was higher than toward carboxymethyl cellulose sodium (395 U mg(-1)), which was different from other family 7 endo-beta-glucanases.
Luo
Huiying
H
Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, People's Republic of China.
Yang
Jun
J
Yang
Peilong
P
Li
Jiang
J
Huang
Huoqing
H
Shi
Pengjun
P
Bai
Yingguo
Y
Wang
Yaru
Y
Fan
Yunliu
Y
Yao
Bin
B
D000595:Amino Acid Sequence; D001203:Ascomycota / Q000201:enzymology* / Q000235:genetics; D003001:Cloning, Molecular; D004271:DNA, Fungal; D044644:Endo-1,3(4)-beta-Glucanase / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics; D005800:Genes, Fungal; D006031:Glycosylation; D006868:Hydrolysis; D008969:Molecular Sequence Data; D010843:Pichia / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
D004271:DNA, Fungal; D005656:Fungal Proteins; D044644:Endo-1,3(4)-beta-Glucanase