[NiFe]-hydrogenases are multimeric proteins. The large subunit contains the NiFe(CN)(2)CO bimetallic active center and the small subunit contains Fe-S clusters. Biosynthesis and assembly of the NiFe(CN)(2)CO active center requires six Hyp accessory proteins. The synthesis of the CN(-) ligands is catalyzed by the combined actions of HypF and HypE using carbamoylphosphate as a substrate. We report the structure of Escherichia coli HypF(92-750) lacking the N-terminal acylphosphatase domain. HypF(92-750) comprises the novel Zn-finger domain, the nucleotide-binding YrdC-like domain, and the Kae1-like universal domain, also binding a nucleotide and a Zn(2+) ion. The two nucleotide-binding sites are sequestered in an internal cavity, facing each other and separated by ∼14 Å. The YrdC-like domain converts carbamoyl moiety to a carbamoyl adenylate intermediate, which is channeled to the Kae1-like domain. Mutations within either nucleotide-binding site compromise hydrogenase maturation but do not affect the carbamoylphosphate phosphatase activity.
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http://dx.doi.org/10.1016/j.str.2011.09.023 | DOI Listing |
Introduction: We present a rare case of long-term survival following metastasectomy for lumbar metastasis with growing teratoma syndrome.
Case Presentation: An 18-year-old man presented with left scrotal mass and lumbago. Alpha-fetoprotein was elevated to 648.
J Biol Chem
October 2024
Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana, USA. Electronic address:
The generation of an active [FeFe]-hydrogenase requires the synthesis of a complex metal center, the H-cluster, by three dedicated maturases: the radical S-adenosyl-l-methionine (SAM) enzymes HydE and HydG, and the GTPase HydF. A key step of [FeFe]-hydrogenase maturation is the synthesis of the dithiomethylamine (DTMA) bridging ligand, a process recently shown to involve the aminomethyl-lipoyl-H-protein from the glycine cleavage system, whose methylamine group originates from serine and ammonium. Here we use functional assays together with electron paramagnetic resonance and electron-nuclear double resonance spectroscopies to show that serine or aspartate together with their respective ammonia-lyase enzymes can provide the nitrogen for DTMA biosynthesis during in vitro [FeFe]-hydrogenase maturation.
View Article and Find Full Text PDFAcc Chem Res
July 2024
Department of Chemistry, University of California, Davis, Davis, California 95616, United States.
ConspectusNature's prototypical hydrogen-forming catalysts─hydrogenases─have attracted much attention because they catalyze hydrogen evolution at near zero overpotential and ambient conditions. Beyond any possible applications in the energy sphere, the hydrogenases feature complicated active sites, which implies novel biosynthetic pathways. In terms of the variety of cofactors, the [FeFe]-hydrogenase is among the most complex.
View Article and Find Full Text PDFJ Am Chem Soc
June 2024
Photobiotechnology, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801 Bochum, Germany.
The active site cofactor of [FeFe]-hydrogenases consists of a cubane [4Fe-4S]-cluster and a unique [2Fe-2S]-cluster, harboring unusual CO- and CN-ligands. The biosynthesis of the [2Fe-2S]-cluster requires three dedicated maturation enzymes called HydG, HydE and HydF. HydG and HydE are both involved in synthesizing a [2Fe-2S]-precursor, still lacking parts of the azadithiolate (adt) moiety that bridge the two iron atoms.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
May 2024
School of Chemical Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
The paper aims to elucidate the final stages in the biosynthesis of the [2Fe] active site of the [FeFe]-hydrogenases. The recently hypothesized intermediate [Fe(SCHNH)(CN)(CO)] ([1]) was prepared by a multistep route from [Fe(S)(CN)(CO)]. The following synthetic intermediates were characterized in order: [Fe(SCHNHFmoc)(CNBEt)(CO)], [Fe(SCHNHFmoc)(CN)-(CO)], and [Fe(SCHNHFmoc)(CN)(CO)], where Fmoc is fluorenylmethoxycarbonyl).
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