Pyruvate : ferredoxin oxidoreductase — new findings on an ancient enzyme

Kerscher, Lorenz; Oesterhelt, Dieter

doi:10.1016/0968-0004(82)90118-9

Cited by 135 publications

(91 citation statements)

References 17 publications

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“…1). The same spacing of consensus cysteine residues was found in other zinc-containing ferredoxin sequences (6,10,11,13,53), and was proposed to be attributed to the similarity of the pattern of hyperfine-shifted resonances of 1 H-NMR spectra of the 7Fe form of zinc-containing ferredoxins 5 to those of the 3Fe-, 4Fe-, and 8Fe-containing ferredoxins (53,54). In the Azotobactertype 7Fe-containing ferredoxins with a long C-terminal region, the cysteine ligand residues are arranged more asymmetrically due to the insertion of a short amino acid sequence stretch at the cluster binding motif (54 -58).…”

mentioning

confidence: 76%

Structural Conservation of the Isolated Zinc Site in Archaeal Zinc-containing Ferredoxins as Revealed by X-ray Absorption Spectroscopic Analysis and Its Evolutionary Implications

Cosper

Stålhandske

Iwasaki

et al. 1999

Journal of Biological Chemistry

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The zfx gene encoding a zinc-containing ferredoxin from Thermoplasma acidophilum strain HO-62 was cloned and sequenced. It is located upstream of two genes encoding an archaeal homolog of nascent polypeptide-associated complex ␣ subunit and a tRNA nucleotidyltransferase. This gene organization is not conserved in several euryarchaeoteal genomes. The multiple sequence alignments of the zfx gene product suggest significant sequence similarity of the ferredoxin core fold to that of a low potential 8Fe-containing dicluster ferredoxin without a zinc center. The tightly bound zinc site of zinc-containing ferredoxins from two phylogenetically distantly related Archaea, T. acidophilum HO-62 and Sulfolobus sp. strain 7, was further investigated by x-ray absorption spectroscopy. The zinc K-edge x-ray absorption spectra of both archaeal ferredoxins are strikingly similar, demonstrating that the same zinc site is found in T. acidophilum ferredoxin as in Sulfolobus sp. ferredoxin, which suggests the structural conservation of isolated zinc binding sites among archaeal zinc-containing ferredoxins. The sequence and spectroscopic data provide the common structural features of the archaeal zinc-containing ferredoxin family.

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mentioning

confidence: 76%

Structural Conservation of the Isolated Zinc Site in Archaeal Zinc-containing Ferredoxins as Revealed by X-ray Absorption Spectroscopic Analysis and Its Evolutionary Implications

Cosper

Stålhandske

Iwasaki

et al. 1999

Journal of Biological Chemistry

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“…Experimental and simulated high-field EPR spectra of PFOR prepared with [3-2 H 3 ]pyruvate and unlabeled or [3][4][5][6][7][8][9][10][11][12][13][14][15] N]TPP are shown in Figure 2. The EPR spectra are rhombic (g x = 2.0079, g y = 2.0053, g z = 2.0021).…”

Section: Epr Spectral Simulations Of the He-tpp Radicalmentioning

confidence: 99%

“…The anisotropy is expected to arise from significant spin density on S1 of the thiazolium ring (30). The g z = 2.0021 peak in the high-field EPR spectrum of the sample prepared with [3- In addition to the 14 N-or 15 N-hyperfine tensor, two isotropic hyperfine interactions (|A iso | = 5G, |A iso | = 3G) are required to account for all the peaks in the corresponding X-band EPR spectra of PFOR prepared with [3-2 H 3 ]pyruvate and unlabeled or [3][4][5][6][7][8][9][10][11][12][13][14][15] N]TPP (Figure 3). These two doublet hyperfine interactions likely arise from one of the H-atoms from each of the two bridging methylene groups that link the pyrophosphate and amino-pyrimidine moieties to the thiazolium ring of TPP (5′-1 H and 3′-1 H, respectively).…”

Section: Epr Spectral Simulations Of the He-tpp Radicalmentioning

confidence: 99%

EPR Spectroscopic and Computational Characterization of the Hydroxyethylidene-Thiamine Pyrophosphate Radical Intermediate of Pyruvate:Ferredoxin Oxidoreductase

et al. 2006

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The radical intermediate of pyruvate:ferredoxin oxidoreductase (PFOR) from Moorella thermoacetica was characterized using electron paramagnetic resonance (EPR) spectroscopy at Xband and D-band microwave frequencies. EPR spectra obtained with various combinations of isotopically labeled substrate (pyruvate) and coenzyme (thiamine pyrophosphate (TPP)), were analyzed by spectral simulations. Parameters obtained from the simulations were compared with those predicted from electronic structure calculations on various radical structures. The g-values and 14 N/ 15 N-hyperfine splittings obtained from the spectra are consistent with a planar, hydroxyethylidene-thiamine pyrophosphate (HE-TPP) π-radical, in which spin is delocalized onto the thiazolium sulfur and nitrogen atoms. The 1 H-hyperfine splittings from the methyl group of pyruvate and the 13 C-hyperfine splittings from C2 of both pyruvate and TPP are consistent with a model in which the pyruvate-derived oxygen atom of the HE-TPP radical forms a hydrogen bond. The hyperfine splitting constants and g-values are not compatible with those predicted for a nonplanar, σ/n-type cation radical.Pyruvate:ferredoxin oxidoreductase (E.C.1.2.7.1) (PFOR 1 ) is a member of the 2-keto acid oxidoreductase family. This enzyme plays a central role in anaerobic fermentative metabolism by catalyzing the reversible, CoA-dependent, oxidative decarboxylation of pyruvate to acetylCoA and CO 2 (3). The two electrons generated in the oxidative reaction are transferred through [4Fe-4S] clusters in PFOR to an oxidized ferredoxin (4). PFOR is found in microbes lacking mitochondria from all three kingdoms (5). PFOR enzymes from different species have been grouped into three types depending on subunit composition (6). The different types of PFOR enzymes have between one and three [4Fe-4S] clusters. clusters are electron transfer cofactors serving as way-stops for electrons exiting the active site in the forward † This work was supported by grants from the National Institutes of Health: GM35752 G.H.R.; GM39451 S.W.R.; DK44083 T.P.B.; and Center Grant 1P20RR17675 to the University of Nebraska. S.O.M was supported by an NIH Predoctoral Training Grant T32 GM 08293. *To whom correspondence should be addressed. Telephone: (608) 262-0509; Fax: (608) 265-2904; Email: reed@biochem.wisc.edu. ‖ Current address: Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520-8066 1 Abbreviations: PFOR, pyruvate:ferredoxin oxidoreductase; CoA, coenzyme A; TPP, thiamine pyrophosphate; HE-TPP, hydroxyethylidene-thiamine pyrophosphate; EPR, electron paramagnetic resonance; ENDOR, electron nuclear double resonance; CW continuous wave; DFT, density functional theory; S/N, signal-to-noise ratio; RMSD, root mean square deviation; POX, pyruvate oxidase. to an acetyl radical followed by radical recombination with a CoA-thiyl radical (11). Elucidation of the structure of the HE-TPP radical intermediate is essential to an eventual understanding of the subsequent steps in the overall reacti...

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“…While it seems from the limited data available that this protein may be a descendant of bacterial homologues, its roots are found in bacteria distant from ␣-proteobacteria (86,91,100,102). Conceivably, this and other hydrogenosomal proteins may have been recruited to the ancestor by horizontal transfer.…”

Section: Hydrogen Exporter-earlymentioning

confidence: 99%

Origin and Evolution of the Mitochondrial Proteome

Kurland

Andersson

2000

Microbiol Mol Biol Rev

364

272

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SUMMARY The endosymbiotic theory for the origin of mitochondria requires substantial modification. The three identifiable ancestral sources to the proteome of mitochondria are proteins descended from the ancestral α-proteobacteria symbiont, proteins with no homology to bacterial orthologs, and diverse proteins with bacterial affinities not derived from α-proteobacteria. Random mutations in the form of deletions large and small seem to have eliminated nonessential genes from the endosymbiont-mitochondrial genome lineages. This process, together with the transfer of genes from the endosymbiont-mitochondrial genome to nuclei, has led to a marked reduction in the size of mitochondrial genomes. All proteins of bacterial descent that are encoded by nuclear genes were probably transferred by the same mechanism, involving the disintegration of mitochondria or bacteria by the intracellular membranous vacuoles of cells to release nucleic acid fragments that transform the nuclear genome. This ongoing process has intermittently introduced bacterial genes to nuclear genomes. The genomes of the last common ancestor of all organisms, in particular of mitochondria, encoded cytochrome oxidase homologues. There are no phylogenetic indications either in the mitochondrial proteome or in the nuclear genomes that the initial or subsequent function of the ancestor to the mitochondria was anaerobic. In contrast, there are indications that relatively advanced eukaryotes adapted to anaerobiosis by dismantling their mitochondria and refitting them as hydrogenosomes. Accordingly, a continuous history of aerobic respiration seems to have been the fate of most mitochondrial lineages. The initial phases of this history may have involved aerobic respiration by the symbiont functioning as a scavenger of toxic oxygen. The transition to mitochondria capable of active ATP export to the host cell seems to have required recruitment of eukaryotic ATP transport proteins from the nucleus. The identity of the ancestral host of the α-proteobacterial endosymbiont is unclear, but there is no indication that it was an autotroph. There are no indications of a specific α-proteobacterial origin to genes for glycolysis. In the absence of data to the contrary, it is assumed that the ancestral host cell was a heterotroph.

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Pyruvate : ferredoxin oxidoreductase — new findings on an ancient enzyme

Cited by 135 publications

References 17 publications

Structural Conservation of the Isolated Zinc Site in Archaeal Zinc-containing Ferredoxins as Revealed by X-ray Absorption Spectroscopic Analysis and Its Evolutionary Implications

Structural Conservation of the Isolated Zinc Site in Archaeal Zinc-containing Ferredoxins as Revealed by X-ray Absorption Spectroscopic Analysis and Its Evolutionary Implications

EPR Spectroscopic and Computational Characterization of the Hydroxyethylidene-Thiamine Pyrophosphate Radical Intermediate of Pyruvate:Ferredoxin Oxidoreductase

Origin and Evolution of the Mitochondrial Proteome

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