Enzyme activity of a Phanerochaete chrysosporium cellobiohydrolase (CBHI.1) expressed as a heterologous protein from Escherichia coli

Abstract

The aim of this study was to produce a secreted, heterologously expressed Phanerochaete 
chrysosporium cellobiohydrolase (CBHI.1) protein that required no in vitro chemical refolding and to 
investigate the cellulolytic activity of the clone expressing the glutathione S- transferase (GST) fused 
CBHI.1 protein. Plate enzyme activity screening of E. coli cells transformed with pGEXcbhI.1 vector on 
carboxy-methyl-cellulose (CMC) produced several clones which produced clearing zones on CMC 
when induced. A randomly selected representative pGEXcbhI.1 clone produced hydrolysis on both 
Avicel and CMC when induced. Crude protein extracts obtained from the induced pGEXcbhI.1 clone 
exhibited time dependent enzymatic activity against both CMC and Avicel.