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Indian Journal of Biotechnology (IJBT) >
IJBT Vol.06 [2007] >
IJBT Vol.06(3) [July 2007] >
| Title: | A unique thermostable lichenase from Thermotoga maritima MSB8 with divergent substrate specificity |
| Authors: | Khan, Mohammed Abdul Sattar
Akbar, Mohammed
Kitaoka, Motomitsu
Hayashi, Kiyoshi |
| Keywords: | Thermotoga maritima
endoglucanase
lichenase
family 5
glucosyl β-1
3 glucosyl β-1
4 glucose
glucosyl β-1
4 glucosyl β-1
3 glucose |
| Issue Date: | Jul-2007 |
| Publisher: | CSIR |
| IPC Code: | Int. Cl.8 C12N9/24 |
| Abstract: | A putative endoglucanase gene corresponding to locus TM 1752 (AAD36817.1, Q9X274) of Thermotoga maritima MSB8 was cloned and expressed in Escherichia coli. The enzyme contains a NEP (Asn-Glu-Pro) motif but lacks a PCD (proposed catalytic domain) block. This endoglucanase is grouped under family 5 of the glycosyl hydrolases members of which predominantly hydrolyze β-1,4-linkages of carbohydrate polymers. The enzyme efficiently hydrolyzes the glycosidic bonds of mixed β-1,3-1,4 linkages in lichenan and barley β-glucan, but did not display any activity on crystalline cellulose or laminarin. However, negligible amount of hydrolysis was observed with CM-cellulose. This enzyme produced glucosyl β-1,3 glucosyl β-1,4 glucose as the major end product and glucosyl β-1,4 glucosyl β-1,3 glucose was not detected. The putative endoglucanase of T. maritima appears to be a unique endoglucanase being the first lichenase producing glucosyl β-1,3 glucosyl β-1,4 glucose to be placed into family 5 of the glucosyl hydrolases. |
| Page(s): | 315-320 |
| ISSN: | 0975-0967 (Online); 0972-5849 (Print) |
| Source: | IJBT Vol.06(3) [July 2007]
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