원문정보
초록
영어
The catalytic activity of oxygenase-based whole-cell biocatalysts are heavily influenced by substrate and product toxicity because of cell membrane permeabilizing effects and protein denaturating effects of lipophilic substrates and products. In this presentation, we will report a novel approach to increase stability of oxygenase-based whole-cell biocatalyst, a recombinant Escherichia coli expressing chnB the gene of cyclohexanone monooxygenase of Acinetobacter calcoaceticus NCIMB 9871. Oxygenation activity of the recombinant E. coli expressing chnB alone was rapidly decreased during biotransformation of cyclohexanone into ε-caprolactone. However, the catalytic activity was rather maintained when the genes encoding chaperones GroEL-ES, DnaKJ-GrpE or ClpB, IbpAB, DnaKJ-GrpE were coexpressed. The chaperoning proteins were assumed to assist protein folding to the native conformation and/or disaggregating unfolded proteins. Thus, we conclude that stability of oxygenase-based whole-cell biocatalysts can be enhanced via coexpression of the genes encoding chaperones.