The coding sequence for the yeast ubiquitin-conjugating enzyme Ubc7 was obtained by PCR from Saccharomyces cerevisiae genomic DNA. This sequence was placed in a plasmid containing the lambdaPL promoter and was used for temperature-regulated expression in Escherichia coli. The expressed 18-kDa protein was isolated in the inclusion body fraction from bacterial lysates, in contrast to the soluble nature of other yeast ubiquitin-conjugating enzymes expressed in E. coli. Selective solubilization of the protein using 5 M urea followed by dialysis, MonoQ FPLC, and Superdex-75 FPLC yielded electrophoretically pure Ubc7 protein. The purified protein was enzymatically active as determined by formation of enzyme-linked thiolester with ubiquitin. The ability of Ubc7 protein to regain enzymatic activity after urea denaturation appears to be attributable to the stable core alpha/beta folded structure common to the ubiquitin-conjugating enzymes whose structures have been determined to date.
|Evidence ID||Analyze ID||Interactor||Interactor Systematic Name||Interactor||Interactor Systematic Name||Type||Assay||Annotation||Action||Modification||Phenotype||Source||Reference||Note|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Gene Ontology Term||Gene Ontology Term ID||Qualifier||Aspect||Method||Evidence||Source||Assigned On||Reference||Annotation Extension|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Phenotype||Experiment Type||Experiment Type Category||Mutant Information||Strain Background||Chemical||Details||Reference|
|Evidence ID||Analyze ID||Regulator||Regulator Systematic Name||Target||Target Systematic Name||Experiment||Conditions||Strain||Source||Reference|