Investigation of the Solubility and Enzymatic Activity of a Thioredoxin-GeloninFusion Protein

摘要

A synthetic gene for the ribosome-inactivating protein (RIP), gelonin, waspreviously engineered and inserted into the pET-21a plasmid under the control of the T7 promoter by researchers at M.D. Anderson Cancer Research Institute in Houston, Texas. Upon induction of Escherichia coli (E. coli) strain BL-21(DE3)pLysS containing this pET-2 1 a/gel plasmid, the resulting gelonin protein forms insoluble aggregates, known as inclusion bodies, and exhibits no activity under the assay conditions tested. By genetically fusing gelonin to the highly stable and soluble protein, thioredoxin, it was thought that there would be an increase in the solubility of gelonin, possibly accompanied by a measurable amount of enzymatic activity.