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

Abstract

To obtain the secreting expression vector, the signal peptide sequence and mature peptide sequence of endoglucanase from BoldItalic KX6 were cloned into the pET28a plasmid. The recombinant vector pET28a/KX6 was transformed BoldItalic 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 BoldItalic KX6 had played a very important role in the secret expression and activity of foreign proteins in the BoldItalic host cell.

Key words： thermotolerant endoglucanase; expression vector; signal peptide; location analysis

Acknowledgements

This study was supported by the project of Sic-Tech Plan of Hebei Province, China (No. 07225553) and the Key Science and Technology Project of the 11th Five-Year-Plan of Hebei Province, China (No. 06220106D).

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