Cloning of endoglucanase genes from Cellulomonas biazotea into E. coli and S. cerevisiae using shuttle vector YEp24

We constructed a SmaI genomic library of Cellulomonas biazotea DNA in E. coli and in the S. cerevisiae shuttle vector, YEP 24. Three clone were identified that conferred the ability for E. coli or S. cerevisiae transformants to produce carboxymethylcellulase (CMCase). Cells transformed with these clones were compared with one another and with nontransformed cells for hyper-production of CMCase. In vivo and in vitro studies indicated that the CMCase genes were fully expressed and the enzyme activity was located extracellularly. The optimum pH and temperature for the CMCase thus cloned were pH 7 and 50 degrees C, respectively, as was the case for the donor.