|
|
|
|
|
|
Substrate-Induced Production and Secretion of Cellulases by Clostridium acetobutylicum. Ana M. López-Contreras, 2004.Clostridium acetobutylicum ATCC 824 is a solventogenic bacterium that grows heterotrophically on a variety of carbohydrates, including glucose, cellobiose, xylose, and lichenan, a linear polymer of ß-1,3- and ß-1,4-linked ß-D-glucose units . C . acetobutylicum does not degrade cellulose, although its genome sequence contains several cellulase-encoding genes and a complete cellulosome cluster of cellulosome genes . In the present study, we demonstrate that a low but significant level of induction of cellulase activity occurs during growth on xylose or lichenan . The celF gene, located in the cellulosome-like gene cluster and coding for a unique cellulase that belongs to glycoside hydrolase family 48, was cloned in Escherichia coli, and antibodies were raised against the overproduced CelF protein . A Western blot analysis suggested a possible catabolite repression by glucose or cellobiose and an up-regulation by lichenan or xylose of the extracellular production of CelF by C . acetobutylicum . Possible reasons for the apparent inability of C . acetobutylicum to degrade cellulose are discussed .
|
© 2005
Transgalactic Ltd (manufacturer of Bioscreen C software) |
Privacy Statement | P.O. Box
1393, 00101 Helsinki, Finland,
Last modified: May 25, 2005
| ||||||
