원문정보
초록
영어
We studied charge engineered ubiquitin as a fusion partner in recombinant E.coli system. The ubiquitin sequence led fusion protein containing target protein to be expressed in a soluble form and/or over expression. The fusion protein is clearly cut at the junction between ubiquitin and target protein by ubiquitin specific protease, so that we could obtain target proteins with an exact N-terminal sequence. For the purpose of efficient purification, we changed the pI of fusion protein by adding polylysine or polyarginine to N-terminal end of modified ubiquitin in which three surface glutamic acids were substituted for arginine or lysine. The fusion proteins expressed in such a recombinant E. coli system were conveniently purified by using ion-exchange chromatographies. Especially in some cases of using on column cleavage system, the production yields of finally purified objective proteins were confirmed to be over 1.0 gram per 1.0 Liter fermentation broth.