원문정보
초록
영어
For the purpose of developing a high-level expression system for production of a human kringle fragment (LK8), secretion pathway engineering was applied by modifying a number of cellular regulations involved in the endoplasmic reticulum homeostasis in a recombinant Saccharomyces cerevisiae strain. Effects of unfolded protein response (UPR) on LK8
production was investigated to see if the coexpression of the HAC1 gene which encoded a
UPR transcription activator enhanced the total expression of LK8. Using the Tn7 transposon yeast library, the ubc6Δ strain was selected as an over-secreting mutant. Thus, partial blocking of polyubiquitination was assumed to accelerate the LK8 secretion since the protein encoded by the UBC6 gene played a role of an ubiquitin conjugation enzyme. On the other hand, in an attempt to develop cost-effective process of LK8 production, both the GAL1 and HXK2 were disrupted and a pattern for LK8 expression was compared in continuous cultures. As a result, the secretion pathway in S. cerevisiae was modified for the enhanced production of LK8. Furthermore, an economic process for LK8 production was developed through strain improvement and fermentation technology.