Isolation of a new cellulase gene from a thermophilic anaerobe and its expression inEscherichia coli |
| |
Authors: | Hiroyuki Honda Takao Saito Shinji Iijima Takeshi Kobayashi |
| |
Affiliation: | (1) Department of Chemical Engineering, Faculty of Engineering, Nagoya University, Chikusa-ku, 464 Nagoya, Japan;(2) Present address: Government Industrial Institute Nagoya, Hirate-cho, Kita-ku, 462 Nagoya, Japan |
| |
Abstract: | 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--d-cellobioside, but could not digest laminarin andp-nitrophenyl--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--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. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|