Kinetic and mutational studies of three NifS homologs from Escherichia coli: mechanistic difference between L-cysteine desulfurase and L-selenocysteine lyase reactions.

@article{Mihara2000KineticAM,
  title={Kinetic and mutational studies of three NifS homologs from Escherichia coli: mechanistic difference between L-cysteine desulfurase and L-selenocysteine lyase reactions.},
  author={H. Mihara and T. Kurihara and T. Yoshimura and N. Esaki},
  journal={Journal of biochemistry},
  year={2000},
  volume={127 4},
  pages={
          559-67
        }
}
We have purified three NifS homologs from Escherichia coli, CSD, CsdB, and IscS, that appear to be involved in iron-sulfur cluster formation and/or the biosynthesis of selenophosphate. All three homologs catalyze the elimination of Se and S from L-selenocysteine and L-cysteine, respectively, to form L-alanine. These pyridoxal 5'-phosphate enzymes were inactivated by abortive transamination, yielding pyruvate and a pyridoxamine 5'-phosphate form of the enzyme. The enzymes showed non-Michaelis… Expand
Escherichia coli NifS-like Proteins Provide Selenium in the Pathway for the Biosynthesis of Selenophosphate*
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The iscS gene is essential for the biosynthesis of 2-selenouridine in tRNA and the selenocysteine-containing formate dehydrogenase H
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  • Chemistry, Medicine
  • Proceedings of the National Academy of Sciences of the United States of America
  • 2002
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isms. Cysteine desulfurase, originally identified in a nitrogen-fixing bacterium, Azotobacter vinelandii, and named NifS, is essential for the production of a holo-form of nitrogenase in vivo. TheExpand
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