ISSN 2756-3391
African Journal of Parasitology Research ISSN 2756-3391 Vol. 8 (2), pp. 001-007, February, 2021. © International Scholars Journals
Full Length Research Paper
A study of the characterization of a glucose dehydrogenase from Bacillus sp. G3 in Escherichia coli
Xuejiao Chen1,2, Haitao Ding1, Yiqing Du1, Hui Lin1, Zeli Li1 and Yuhua Zhao1*
1Institute of Microbiology, College of Life Science, Zhejiang University, Hangzhou 310058, China.
2Hangzhou Wahaha Group Co., Ltd, Hangzhou 310000, China.
Accepted 17 October, 2020
Abstract
The glucose dehydrogenase gene (gdh), cloned from Bacillus sp. G3, was composed of 786 bp nucleotide and the deduced protein molecular mass of one subunit was 28.1 kDa. The recombinant glucose dehydrogenase (rGDH-G3) was functionally expressed in Escherichia coli. The results revealed that expressed rGDH-G3 had a high specific activity of 371.9 U/mg at 25°C and pH 8.0, with oxidized nicotinamide adenine dinucleotide (NAD+) as the cofactor. The enzyme was optimally active at 40°C and pH 9.0. The enzyme displayed broad specificity for other sugars such as D-galactose or maltose. The catalytic efficiency of the rGDH-G3 would be improved 4 times when oxidized nicotinamide adenine dinucleotide phosphate (NADP+) was used as cofactor instead of NAD+.
Key words: Bacillus sp. G3, enzymatic property, glucose dehydrogenase, inverse polymerase chain reaction (IPCR), optimal pH.