ISSN:
1432-0614
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Summary A new cellulase gene was cloned and expressed inEscherichia coli from a thermophilic anaerobe, strain NA10. A 7.4 kbEcoRI fragment of NA10 DNA encoded the cellulase which hydrolyzed carboxymethyl cellulose, lichenan, andp-nitrophenyl-β-d-cellobioside, but could not digest laminarin andp-nitrophenyl-β-d-glucoside. The cloned enzyme could digest cellooligosaccharides and release cellobiose as a main product from cellotetraose but could not digest cellobiose. It was distinct from the endoglucanase which was cloned by us previously from NA10 strain in terms ofp-nitrophenyl-β-d-cellobioside degradation activity and the location of restriction enzyme sites. The enzyme produced byE. coli transformant was extremely heat-stable and the optimum temperature for the enzymatic reaction was 80°C. Fifty three percent of the cloned enzyme was detected in the periplasm and the remaining activity existed in the cellular fraction in theE. coli transformant.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01982914
