A novel endo-glucanase from the thermophilic bacterium Geobacillus sp. 70PC53 with high activity and stability over a broad range of temperatures.
A thermophilic Geobacillus bacterium secreting high activity of endo-glucanase (EC 3.2.1.4) was isolated from rice straw compost supplemented with pig manure. A full-length gene of 1,104 bp, celA, encoding this glycosyl hydrolase family 5 endo-glucanase of 368 amino acids was isolated. No related gene from Geobacillus has been reported previously. The recombinant CelA expressed in Escherichia coli had an optimal activity at 65 degrees C and pH 5.0, and it exhibited tenfold greater specific activity than the commercially available Trichoderma reesei endo-glucanase. CelA displayed activity over a broad temperature range from 45 to 75 degrees C and was a thermostable enzyme with 90% activity retained after heating at 65 degrees C for 6 h. Interestingly, CelA activity could be enhanced by 100% in the presence of 2 mM MnSO(4). CelA had high specific activity over beta-D-glucan from barley and Lichenan, making it a potentially useful enzyme in biofuel and food industries.
Ng
I-Son
IS
Biotechnology Center in Southern Taiwan, Academia Sinica, 2F, No. 22, Lane 31, Sec. 1, Huandong Rd., Sinshih Township, Tainan, 74146, Taiwan, ROC. yswu2001@msn.com
Li
Chen-Wei
CW
Yeh
Yi-Fang
YF
Chen
Po Ting
PT
Chir
Jiun-Ly
JL
Ma
Chin-Hua
CH
Yu
Su-May
SM
Ho
Tuan-hua David
TH
Tong
Chii-Gong
CG
D000595:Amino Acid Sequence; D001407:Bacillus / Q000201:enzymology* / Q000235:genetics; D001483:Base Sequence; D017931:DNA Primers; D004275:DNA, Ribosomal / Q000235:genetics; D004795:Enzyme Stability; D004926:Escherichia coli / Q000235:genetics; D006026:Glycoside Hydrolases / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D013379:Substrate Specificity; D013696:Temperature
D017931:DNA Primers; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D011994:Recombinant Proteins; D006026:Glycoside Hydrolases