{
   "source_x": "PMC",
   "title": "A SUMO-GROUCHO Q DOMAIN FUSION PROTEIN: CHARACTERIZATION AND IN VIVO ULP1-MEDIATED CLEAVAGE",
   "doi": "http://dx.doi.org/10.1016/j.pep.2010.08.008",
   "pmcid": "PMC3005967",
   "abstract": "We describe here a system for the expression and purification of small ubiquitin-related modifier (SUMO) fusion proteins, which often exhibit dramatically increased solubility and stability during expression in bacteria relative to unfused proteins. The vector described here allows expression of a His-tagged protein of interest fused at its N-terminus to SUMO. Using this vector, we have produced a polypeptide consisting of SUMO fused to the Q-domain of Drosophila Groucho in a concentrated soluble form. Hydrodynamic analysis shows that, consistent with previous studies on full-length Groucho, the fusion protein forms an elongated tetramer, as well as higher order oligomers. After expressing a protein as a fusion to SUMO, it is often desirable to cleave the SUMO off of the fusion protein using a SUMO-specific protease such as Ulp1. To facilitate such processing, we have constructed a dual expression vector encoding two fusion proteins: one consisting of SUMO fused to Ulp1 and a second consisting of SUMO fused to a His-tagged protein of interest. The SUMO-Ulp1 cleaves both itself and the other SUMO fusion protein in the bacterial cells prior to lysis, and the proteins retain solubility after cleavage.",
   "authors": [
      "['Kuo, Dennis', 'Nie, Minghua', 'De Hoff, Peter', 'Chambers, Michael', 'Phillips, Martin', 'Hirsch, Ann M.', 'Courey, Albert J.']"
   ],
   "id": "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3005967"
}