Construction of the expression vector and location analysis of thermotolerant endoglucanase in E. coli

摘要

To obtain the secreting expression vector, the signal peptide sequence and mature peptide sequence of endoglucanase from Streptomyces xylophagus KX6 were cloned into the pET28a plasmid. The recombinant vector pET28a/KX6 was transformed Escherichia coli Rosetta (DE3), and the transformant was induced by IPTG. The expression products were primarily distributed in the medium fluid of host cell in a soluble form and the activity was higher than that of other fractions. Both location analysis of targeting protein and activity analysis showed that the signal peptide of endoglucanase from S. xylophagus KX6 had played a very important role in the secret expression and activity of foreign proteins in the E. coli host cell.