Cloning and heterologous expression of a Methanococcus vannielii gene encoding a selenium-binding protein.
The activation and incorporation of selenium into selenocysteine containing selenoproteins has been well established in an Escherichia coli model system but there is little specific information concerning the transport and intracellular trafficking of selenium in biological systems in general. A selenium transport role is a possible function of a novel 42 kDa selenium-binding protein that recently was purified from Methanococcus vannielii. The gene encoding a monomer of this protein (Sbp) has been cloned, sequenced and heterologously expressed in E. coli. The 8.8 kDa gene product contains 81 amino acids. The recombinant Sbp (rSbp) protein was shown to bind selenium from added selenite. The bound selenium appeared predominantly in dimeric and tetrameric forms of the protein. The gene encoding Sbp occurs in an operon that contains a carbonic anhydrase gene and selenocysteine-containing formate dehydrogenase genes, suggesting possible roles in selenium-dependent formate metabolism.
Self
William T
WT
Laboratory of Biochemistry, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892-8012, USA.
Pierce
Renee
R
Stadtman
T C
TC
D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000235:genetics* / Q000378:metabolism*; D003001:Cloning, Molecular; D019281:Dimerization; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism; D005560:Formate Dehydrogenases / Q000378:metabolism; D017017:Methanococcus / Q000235:genetics*; D008957:Models, Genetic; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D011994:Recombinant Proteins / Q000737:chemistry; D012643:Selenium / Q000378:metabolism*; D051137:Selenium-Binding Proteins; D017386:Sequence Homology, Amino Acid
D002352:Carrier Proteins; D011994:Recombinant Proteins; D051137:Selenium-Binding Proteins; D005560:Formate Dehydrogenases; D012643:Selenium