Investigation on stability of transporter protein, glucuronide transporter from Escherichia coli.
The glucuronide transporter GusB, the product of the gusB gene from Escherichia coli, is responsible for detoxification of metabolites. In this study, we successfully expressed GusB homologously in E. coli and investigated its oligomeric state in n-dodecyl-beta-D: -maltoside (DDM) detergent solution. Evidence for a pentameric state with a Stokes radius of 57 +/- 2 A for the purified GusB protein in DDM solution was obtained by analytical size-exclusion HPLC. The elution peak corresponding to pentameric GusB is commonly seen in elution profiles in the different buffer systems examined over a wide pH range. Hence, it is likely that GusB resides in the membrane as a pentamer. Stability studies with different incubation periods with the typical lipids, such as dimyristoylphosphatidylcholine, and total E. coli phospholipids, as the representatives of both phosphatidylcholine and phosphatidylethanolamine, show some clues to two-dimensional crystallization of GusB with lipids.
Ishii
Noriyuki
N
Biological Information Research Center, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan. ishii@ni.aist.go.jp
D000595:Amino Acid Sequence; D002850:Chromatography, Gel; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D026901:Membrane Transport Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D008854:Microscopy, Electron; D008954:Models, Biological; D008969:Molecular Sequence Data; D055503:Protein Multimerization; D055550:Protein Stability
D029968:Escherichia coli Proteins; C499989:GusB protein, E coli; D026901:Membrane Transport Proteins