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Meyer J. Iron-sulfur protein folds, iron-sulfur chemistry, and evolution. J Biol Inorg Chem 2007; 13:157-70. [PMID: 17992543 DOI: 10.1007/s00775-007-0318-7] [Citation(s) in RCA: 176] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2007] [Accepted: 10/25/2007] [Indexed: 11/28/2022]
Abstract
An inventory of unique local protein folds around Fe-S clusters has been derived from the analysis of protein structure databases. Nearly 50 such folds have been identified, and over 90% of them harbor low-potential [2Fe-2S](2+,+) or [4Fe-4S](2+,+) clusters. In contrast, high-potential Fe-S clusters, notwithstanding their structural diversity, occur in only three different protein folds. These observations suggest that the extant population of Fe-S protein folds has to a large extent been shaped in the reducing iron- and sulfur-rich environment that is believed to have predominated on this planet until approximately two billion years ago. High-potential active sites are then surmised to be rarer because they emerged later, in a more oxidizing biosphere, in conditions where iron and sulfide had become poorly available, Fe-S clusters were less stable, and in addition faced competition from heme iron and copper active sites. Among the low-potential Fe-S active sites, protein folds hosting [4Fe-4S](2+,+) clusters outnumber those with [2Fe-2S](2+,+) ones by a factor of 3 at least. This is in keeping with the higher chemical stability and versatility of the tetranuclear clusters, compared with the binuclear ones. It is therefore suggested that, at least while novel Fe-S sites are evolving within proteins, the intrinsic chemical stability of the inorganic moiety may be more important than the stabilizing effect of the polypeptide chain. The discovery rate of novel Fe-S-containing protein folds underwent a sharp increase around 1995, and has remained stable to this day. The current trend suggests that the mapping of the Fe-S fold space is not near completion, in agreement with predictions made for protein folds in general. Altogether, the data collected and analyzed here suggest that the extant structural landscape of Fe-S proteins has been shaped to a large extent by primeval geochemical conditions on one hand, and iron-sulfur chemistry on the other.
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Affiliation(s)
- Jacques Meyer
- Commissariat à l'Energie Atomique, Université Joseph Fourier, UMR5249, CEA-Grenoble, 38054, Grenoble, France.
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Gao H, Carroll KS, Chen H, Bertozzi CR, Leary J. Noncovalent complexes of APS reductase from M. tuberculosis: delineating a mechanistic model using ESI-FTICR MS. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2007; 18:167-78. [PMID: 17023175 PMCID: PMC2755055 DOI: 10.1016/j.jasms.2006.08.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2006] [Revised: 08/16/2006] [Accepted: 08/17/2006] [Indexed: 05/12/2023]
Abstract
ESI-FTICR MS was utilized to characterize a 4Fe-4S containing protein Mycobacterium tuberculosis APS reductase. This enzyme catalyzes the reduction of APS to sulfite and AMP with reducing equivalents from the protein cofactor, thioredoxin. Under nondenaturing conditions, a distribution of the apoprotein, a 2Fe-2S intermediate, and the 4Fe-4S holoprotein were observed. Accurate mass measurements indicated an oxidation state of +2 for the 4Fe-4S cluster, with no disulfide bond in the holoenzyme. Gas-phase stability of the 4Fe-4S cluster was investigated using both in-source and collision induced dissociation, which provided information regarding the relative gas-phase binding strength of iron towards protein ligands and inorganic sulfides. Noncovalent complexes of the holoprotein with several ligands, including APS, thioredoxin, and AMP, were also investigated. Calculated values of dissociation constants for the complexes indicate that AMP binds with a higher affinity to the enzyme intermediate than to the free enzyme. The implications of the binary and ternary complexes observed by gas-phase noncovalent interactions in the mechanism of APS reduction are discussed.
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Affiliation(s)
- Hong Gao
- Section of Molecular Cell Biology and Department of Chemistry, University of California, Davis, CA 95616
- Department of Chemistry, University of California, Berkeley, CA 94720
| | - Kate S. Carroll
- Department of Chemistry, University of California, Berkeley, CA 94720
| | - Huiyi Chen
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
| | - Carolyn R. Bertozzi
- Department of Chemistry, University of California, Berkeley, CA 94720
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
- Howard Hughes Medical Institute
| | - Julie Leary
- Section of Molecular Cell Biology and Department of Chemistry, University of California, Davis, CA 95616
- Correspondence should be addressed to: Julie A. Leary, Genome Center, One Shields Ave, Davis, CA 95616, USA, , Tel: 530-754-4987, Fax: 530-754-8370
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Buchanan BB, Arnon DI. Ferredoxins: chemistry and function in photosynthesis, nitrogen fixation, and fermentative metabolism. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 33:119-76. [PMID: 4393906 DOI: 10.1002/9780470122785.ch3] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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55
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Ulmer DD, Vallee BL. Extrinsic cotton effects and the mechanism of enzyme action. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 27:37-104. [PMID: 4303033 DOI: 10.1002/9780470122723.ch2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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56
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Mortenson LE, Seefeldt LC, Morgan TV, Bolin JT. The role of metal clusters and MgATP in nitrogenase catalysis. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 67:299-374. [PMID: 8322617 DOI: 10.1002/9780470123133.ch4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- L E Mortenson
- Center for Metalloenzyme Studies, University of Georgia, Athens
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57
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Boardman NK. The photochemical systems of photosynthesis. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 30:1-79. [PMID: 4872299 DOI: 10.1002/9780470122754.ch1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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58
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Chance B, Pietro AS. ON THE LIGHT-INDUCED BLEACHING OF PHOTOSYNTHETIC PYRIDINE NUCLEOTIDE REDUCTASE IN THE PRESENCE OF CHLOROPLASTS. Proc Natl Acad Sci U S A 2006; 49:633-8. [PMID: 16591080 PMCID: PMC299941 DOI: 10.1073/pnas.49.5.633] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- B Chance
- JOHNSON RESEARCH FOUNDATION, UNIVERSITY OF PENNSYLVANIA, PHILADELPHIA
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59
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Valentine RC, Brill WJ, Wolfe RS. ROLE OF FERREDOXIN IN PYRIDINE NUCLEOTIDE REDUCTION. Proc Natl Acad Sci U S A 2006; 48:1856-60. [PMID: 16591011 PMCID: PMC221051 DOI: 10.1073/pnas.48.10.1856] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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60
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Park YJ, Yoo CB, Choi SY, Lee HB. Purifications and characterizations of a ferredoxin and its related 2-oxoacid:ferredoxin oxidoreductase from the hyperthermophilic archaeon, Sulfolobus solfataricus P1. BMB Rep 2006; 39:46-54. [PMID: 16466637 DOI: 10.5483/bmbrep.2006.39.1.046] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The coenzyme A-acylating 2-oxoacid:ferredoxin oxidoreductase and ferredoxin (an effective electron acceptor) were purified from the hyperthermophilic archaeon, Sulfolobus solfataricus P1 (DSM1616). The purified ferredoxin is a monomeric protein with an apparent molecular mass of approximately 11 kDa by SDS-PAGE and of 11,180+/-50 Da by MALDI-TOF mass spectrometry. Ferredoxin was identified to be a dicluster, [3Fe-4S][4Fe-4S], type ferredoxin by spectrophotometric and EPR studies, and appeared to be zinc-containing based on the shared homology of its N-terminal sequence with those of known zinc-containing ferredoxins. On the other hand, the purified 2-oxoacid: ferredoxin oxidoreductase was found to be a heterodimeric enzyme consisting of 69 kDa alpha and 34 kDa beta subunits by SDS-PAGE and MALDI-TOF mass spectrometry. The purified enzyme showed a specific activity of 52.6 units/mg for the reduction of cytochrome c with 2-oxoglutarate as substrate at 55 degrees C, pH 7.0. Maximum activity was observed at 70 degrees C and the optimum pH for enzymatic activity was 7.0 -8.0. The enzyme displays broad substrate specificity toward 2-oxoacids, such as pyruvate, 2-oxobutyrate, and 2-oxoglutarate. Among the 2-oxoacids tested (pyruvate, 2-oxobutyrate, and 2-oxoglutarate), 2-oxoglutarate was found to be the best substrate with Km and kcat values of 163 microM and 452 min(-1), respectively. These results provide useful information for structural studies on these two proteins and for studies on the mechanism of electron transfer between the two.
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Affiliation(s)
- Young-Jun Park
- Department of Biochemistry, College of Natural Sciences, Kangwon National University, Chuncheon, 200-701, Korea
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61
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Anderson RC, Majak W, Rassmussen MA, Callaway TR, Beier RC, Nisbet DJ, Allison MJ. Toxicity and metabolism of the conjugates of 3-nitropropanol and 3-nitropropionic acid in forages poisonous to livestock. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2005; 53:2344-2350. [PMID: 15769179 DOI: 10.1021/jf040392j] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Glycosides of 3-nitro-1-propanol (nitropropanol) and glucose esters of 3-nitro-1-propanoic acid (nitropropionic acid) occur in many forages distributed throughout the world. Systemically, nitropropionic acid irreversibly inactivates succinate dehydrogenase, thereby blocking ATP formation. Nitropropanol is not toxic per se in mammals but is converted to nitropropionic acid by hepatic alcohol dehydrogenase. Nitrotoxins can be metabolized by rumen microbes, which may provide a mechanism for detoxification. At least 20 different ruminal bacteria are known to metabolize the nitrotoxins, but most appear to play a minor role in detoxification. Evidence suggests that an obligate anaerobic nitro-respiring bacterium, Denitrobacterium detoxificans, may be particularly important in conferring protection to animals consuming the nitrotoxins as this bacterium metabolizes the toxins at rates near those by mixed ruminal populations. Rates of ruminal nitrotoxin metabolism can be enhanced by modifying the rumen environment through dietary manipulations, which suggests in vivo enrichment of competent nitrotoxin-metabolizing bacteria such as D. detoxificans.
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Affiliation(s)
- Robin C Anderson
- Food and Feed Safety Research Unit, Southern Plains Agricultural Research Center, Agricultural Research Service, U.S. Department of Agriculture, 2881 F&B Road, College Station, Texas 77845, USA.
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62
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Higgins CL, Wittung-Stafshede P. Formation of linear three-iron clusters in Aquifex aeolicus two-iron ferredoxins: effect of protein-unfolding speed. Arch Biochem Biophys 2004; 427:154-63. [PMID: 15196989 DOI: 10.1016/j.abb.2004.04.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2004] [Revised: 04/22/2004] [Indexed: 10/26/2022]
Abstract
The presence of a linear [3Fe-4S] cluster in a protein was first observed in beef-heart aconitase. Here, we report the formation of linear [3Fe-4S] clusters upon guanidine hydrochloride (GuHCl)-induced unfolding of Aquifex aeolicus [2Fe-2S] ferredoxins (Fd) (AaeFd1, AaeFd4, and AaeFd5) at alkaline conditions (pH 10, 20 degrees C). We find the mechanism of linear [3Fe-4S] cluster formation to depend critically on the speed of polypeptide unfolding. In similarity to seven-iron Fds, polypeptide unfolding determines the rate by which linear [3Fe-4S] clusters form in AaeFd4 and AaeFd5. In contrast, in a disulfide-lacking variant of AaeFd1, which unfolds faster than AaeFd4 and AaeFd5, the polypeptides unfold first and the majority of clusters decompose. Next, unfolded polypeptides retaining intact clusters scavenge iron and sulfur to form linear [3Fe-4S] clusters in a bimolecular reaction. Wild-type AaeFd1 unfolds slower than the speed of linear-cluster decomposition, and the linear species is never populated. Linear [3Fe-4S] clusters may be intermediates during folding of iron-sulfur proteins.
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63
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Kaji M, Matsushita O, Tamai E, Miyata S, Taniguchi Y, Shimamoto S, Katayama S, Morita S, Okabe A. A novel type of DNA curvature present in a Clostridium perfringens ferredoxin gene: characterization and role in gene expression. MICROBIOLOGY-SGM 2004; 149:3083-3091. [PMID: 14600220 DOI: 10.1099/mic.0.26503-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This study has revealed that a Clostridium perfringens ferredoxin gene (per-fdx) possesses a novel type of DNA curvature, which is formed by five phased A-tracts extending from upstream to downstream of the -35 region. The three A-tracts upstream of the promoter and the two within the promoter are located at the positions corresponding to A-tracts present in a C. perfringens phospholipase C gene (plc) and a Clostridium pasteurianum ferredoxin gene (pas-fdx), respectively. DNA fragments of the per-fdx, pas-fdx and plc genes (nucleotide positions -69 to +1 relative to the transcription initiation site) were fused to a chloramphenicol acetyltransferase reporter gene on a plasmid, pPSV, and their in vivo promoter activities were examined by assaying the chloramphenicol acetyltransferase activity of each C. perfringens transformant. Comparison of the three constructs showed that the order of promoter activity is, in descending order, per-fdx, pas-fdx and plc. Deletion of the three upstream A-tracts of the per-fdx gene drastically decreased the promoter activity, as demonstrated previously for the plc promoter. Substitution of the most downstream A-tract decreased the promoter activities of the per-fdx and pas-fdx genes. These results indicate that not only the phased A-tracts upstream of the promoter but also those within the promoter stimulate the promoter activity, and suggest that the high activity of the per-fdx promoter is due to the combined effects of these two types of A-tracts.
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Affiliation(s)
- Masato Kaji
- Department of Hospital Pharmacy, Kagawa Medical University, 1750-1, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
| | - Osamu Matsushita
- Department of Microbiology, Kagawa Medical University, 1750-1, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
| | - Eiji Tamai
- Department of Microbiology, Kagawa Medical University, 1750-1, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
| | - Shigeru Miyata
- Department of Microbiology, Kagawa Medical University, 1750-1, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
| | - Yuki Taniguchi
- Department of Microbiology, Kagawa Medical University, 1750-1, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
| | - Seiko Shimamoto
- Department of Microbiology, Kagawa Medical University, 1750-1, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
| | - Seiichi Katayama
- Department of Biochemistry, Faculty of Science, Okayama University of Science, 1-1, Ridai-cho, Okayama 700-0005, Japan
| | - Shushi Morita
- Department of Hospital Pharmacy, Kagawa Medical University, 1750-1, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
| | - Akinobu Okabe
- Department of Microbiology, Kagawa Medical University, 1750-1, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
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64
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Griffin S, Higgins CL, Soulimane T, Wittung-Stafshede P. High thermal and chemical stability of Thermus thermophilus seven-iron ferredoxin. Linear clusters form at high pH on polypeptide unfolding. ACTA ACUST UNITED AC 2004; 270:4736-43. [PMID: 14622262 DOI: 10.1046/j.1432-1033.2003.03873.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To probe the stability of the seven-iron ferredoxin from Thermus thermophilus (FdTt), we investigated its chemical and thermal denaturation processes in solution. As predicted from the crystal structure, FdTt is extremely resistant to perturbation. The guanidine hydrochloride-induced unfolding transition shows a midpoint at 6.5 m (pH 7, 20 degrees C), and the thermal midpoint is above boiling, at 114 degrees C. The stability of FdTt is much lower at acidic pH, suggesting that electrostatic interactions are important for the high stability at higher pH. On FdTt unfolding at alkaline pH, new absorption bands at 520 nm and 610 nm appear transiently, resulting from rearrangement of the cubic clusters into linear three-iron species. A range of iron-sulfur proteins has been found to accommodate these novel clusters in vitro, although no biological function has yet been assigned.
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Affiliation(s)
- Susanne Griffin
- Department of Chemistry, Tulane University, New Orleans, LA, USA Paul Scherrer Institute, Structural Biology, Villigen, Switzerland
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65
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Hanke GT, Kimata-Ariga Y, Taniguchi I, Hase T. A post genomic characterization of Arabidopsis ferredoxins. PLANT PHYSIOLOGY 2004; 134:255-64. [PMID: 14684843 PMCID: PMC316305 DOI: 10.1104/pp.103.032755] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2003] [Revised: 09/30/2003] [Accepted: 10/12/2003] [Indexed: 05/18/2023]
Abstract
In higher plant plastids, ferredoxin (Fd) is the unique soluble electron carrier protein located in the stroma. Consequently, a wide variety of essential metabolic and signaling processes depend upon reduction by Fd. The currently available plant genomes of Arabidopsis and rice (Oryza sativa) contain several genes encoding putative Fds, although little is known about the proteins themselves. To establish whether this variety represents redundancy or specialized function, we have recombinantly expressed and purified the four conventional [2Fe-2S] Fd proteins encoded in the Arabidopsis genome and analyzed their physical and functional properties. Two proteins are leaf type Fds, having relatively low redox potentials and supporting a higher photosynthetic activity. One protein is a root type Fd, being more efficiently reduced under nonphotosynthetic conditions and supporting a higher activity of sulfite reduction. A further Fd has a remarkably positive redox potential and so, although redox active, is limited in redox partners to which it can donate electrons. Immunological analysis indicates that all four proteins are expressed in mature leaves. This holistic view demonstrates how varied and essential soluble electron transfer functions in higher plants are fulfilled through a diversity of Fd proteins.
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Affiliation(s)
- Guy Thomas Hanke
- Division of Enzymology, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
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66
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Affiliation(s)
- Stephen W Ragsdale
- Department of Biochemistry, Beadle Center, 19th and Vine Streets, University of Nebraska, Lincoln, Nebraska 68588-0664, USA.
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67
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Yeh AP, Ambroggio XI, Andrade SLA, Einsle O, Chatelet C, Meyer J, Rees DC. High resolution crystal structures of the wild type and Cys-55-->Ser and Cys-59-->Ser variants of the thioredoxin-like [2Fe-2S] ferredoxin from Aquifex aeolicus. J Biol Chem 2002; 277:34499-507. [PMID: 12089152 DOI: 10.1074/jbc.m205096200] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The [2Fe-2S] ferredoxin (Fd4) from Aquifex aeolicus adopts a thioredoxin-like polypeptide fold that is distinct from other [2Fe-2S] ferredoxins. Crystal structures of the Cys-55 --> Ser (C55S) and Cys-59 --> Ser (C59S) variants of this protein have been determined to 1.25 A and 1.05 A resolution, respectively, whereas the resolution of the wild type (WT) has been extended to 1.5 A. The improved WT structure provides a detailed description of the [2Fe-2S] cluster, including two features that have not been noted previously in any [2Fe-2S] cluster-containing protein, namely, pronounced distortions in the cysteine coordination to the cluster and a Calpha-H-Sgamma hydrogen bond between cluster ligands Cys-55 and Cys-9. These features may contribute to the unusual electronic and magnetic properties of the [2Fe-2S] clusters in WT and variants of this ferredoxin. The structures of the two variants of Fd4, in which single cysteine ligands to the [2Fe-2S] cluster are replaced by serine, establish the metric details of serine-ligated Fe-S active sites with unprecedented accuracy. Both the cluster and its surrounding protein matrix change in subtle ways to accommodate this ligand substitution, particularly in terms of distortions of the Fe(2)S(2) inorganic core from planarity and displacements of the polypeptide chain. These high resolution structures illustrate how the interactions between polypeptide chains and Fe-S active sites reflect combinations of flexibility and rigidity on the part of both partners; these themes are also evident in more complex systems, as exemplified by changes associated with serine ligation of the nitrogenase P cluster.
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Affiliation(s)
- Andrew P Yeh
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
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68
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Beinert H. Spectroscopy of succinate dehydrogenases, a historical perspective. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1553:7-22. [PMID: 11803014 DOI: 10.1016/s0005-2728(01)00235-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
An attempt is made to retrace, from personal experience, the discovery of redox-reactive non-heme iron in living matter, which turned out to occur in the form of iron-sulfur (Fe-S) clusters, and then to recount the immediate application of this knowledge in exploring the composition of the mitochondrial respiratory chain, and in the rather detailed description of the workings of its components and, for the purposes of the present volume, of succinate dehydrogenase. The relationship of these events to the general status of technology and the available methodology and instrumentation is considered in some detail, with the conclusion that there scarcely was a way that these discoveries could have been made earlier. It is then shown how methods, techniques and interpretations of results were developed and evolved during the applications that were made to a complex problem such as that of the composition, structure and functioning of succinate dehydrogenase. A tabulation of the most significant events--concerning specifically spectroscopy and its interpretations--in this development is given up to the year 2000.
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Affiliation(s)
- Helmut Beinert
- Institute for Enzyme Research and Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin-Madison, 1710 University Avenue, Madison, WI 53705-4098, USA.
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69
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Abstract
Most low-potential ferredoxins (Fds) are of the well-known [2Fe-2S] plant or [4Fe-4S] bacterial type. Yet, an additional class of [2Fe-2S] Fds has been recognized on the basis of sequence and spectroscopic idiosyncrasies. A recent crystal structure has confirmed the uniqueness of this third kind of Fd, and shown that these proteins display an unexpected structural similarity to thioredoxin. The properties of these thioredoxin-like [2Fe-2S] Fds are summarized, and hypotheses concerning their function are discussed.
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Affiliation(s)
- J Meyer
- Laboratoire de Bioénergétique Cellulaire et Pathologique, Département de Biologie Moléculaire et Structurale, CEA-Grenoble, 38054, Grenoble, France.
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70
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Jung YS, Gao-Sheridan HS, Christiansen J, Dean DR, Burgess BK. Purification and biophysical characterization of a new [2Fe-2S] ferredoxin from Azotobacter vinelandii, a putative [Fe-S] cluster assembly/repair protein. J Biol Chem 1999; 274:32402-10. [PMID: 10542283 DOI: 10.1074/jbc.274.45.32402] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
During the purification of site-directed mutant variants of Azotobacter vinelandii ferredoxin I (FdI), a pink protein, which was not observed in native FdI preparations, appeared to associate specifically with variants that had mutations in ligands to FdI [Fe-S] clusters. That protein, which we designate FdIV, has now been purified. NH(2)-terminal sequence analysis revealed that the protein is the product of a previously described gene, herein designated fdxD, that is in the A. vinelandii iscSUA operon that encodes proteins involved in iron-sulfur cluster assembly or repair. An apoprotein molecular mass of 12,434.03 +/- 0.21 Da was determined by mass spectrometry consistent with the known gene sequence. The monomeric protein was shown to contain a single [2Fe-2S](2+/+) cluster by UV/visible, CD, and EPR spectroscopies with a reduction potential of -344 mV versus the standard hydrogen electrode. When overexpressed in Escherichia coli, recombinant FdIV holoprotein was successfully assembled. However, the polypeptide of the recombinant protein was modified in some way such that the apoprotein molecular mass increased by 52 Da. Antibodies raised against FdIV and EPR spectroscopy were used to examine the relative levels of FdIV and FdI in various A. vinelandii strains leading to the conclusion that FdIV levels appear to be specifically increased under conditions where another protein, NADPH:ferredoxin reductase is also up-regulated. In that case, the fpr gene is known to be activated in response to oxidative stress. This suggests that the fdxD gene and other genes in the iron-sulfur cluster assembly or repair operon might be similarly up-regulated in response to oxidative stress.
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Affiliation(s)
- Y S Jung
- Department of Molecular Biology, University of California, Irvine, California 92697, USA
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72
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Studies of hyperfine interactions in [2Fe2S] proteins by EPR and double resonance spectroscopy. Coord Chem Rev 1999. [DOI: 10.1016/s0010-8545(99)00155-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Brereton PS, Maher MJ, Tregloan PA, Wedd AG. Investigation of the role of surface residues in the ferredoxin from Clostridium pasteurianum. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1429:307-16. [PMID: 9989216 DOI: 10.1016/s0167-4838(98)00197-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Eleven mutant forms of the ferredoxin from Clostridium pasteurianum (CpFd; 2 Fe4S4; 6200 Da) have been isolated in which six surface carboxylates are changed systematically to their uncharged but stereochemically equivalent carboxamide analogues. Such changes provide molecules which vary in overall charge and its surface distribution but vary minimally in structure and reduction potential. Glu-17 and Asp-6, -27, -33, -35, and -39 were converted providing six single mutants, four double mutants and one triple mutant. The proteins were characterised by UV-visible spectroscopy, square-wave voltammetry and 1H NMR. Their ability to mediate electron transfer between spinach NADH:ferredoxin oxidoreductase and horse heart cytochrome c was assessed. Each mutant is 30-100% as active as the recombinant protein with the triple mutant D33,35,39N being least active. Second-order rate constants k2 for the oxidation of reduced mutant ferredoxins by [Co(NH3)6]3+ were measured at 25 degrees C and I = 0.1 M by stopped-flow techniques. Each mutant displayed saturation kinetics with k2 being 30-100% of that for the recombinant protein. The rates were moderately sensitive to ionic strength. Variation in association constant K could not be detected within the confidence limits of the data. Overall the effects of the mutations were minor. In contrast to human and Anabaena 7120 [Fe2S2]-ferredoxins, electron transfer does not appear to rely on the presence of one or two specific surface carboxylate residues. It may occur from multiple sites on the surface of CpFd with recognition processes for its many physiological redox partners being controlled by relative reduction potentials, in addition to unidentified criteria. The conclusions are consistent with previous results for another series of mutant CpFd proteins interacting with physiological redox partners pyruvate: Fd oxidoreductase and hydrogenase (J.M. Moulis, V. Davasse (1995) Biochemistry 34, 16781-16788).
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Affiliation(s)
- P S Brereton
- School of Chemistry, University of Melbourne, Parkville, Victoria, Australia
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74
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Schoepp B, Brugna M, Lebrun E, Nitschke W. Iron-Sulfur Centers Involved in Photosynthetic Light Reactions. ADVANCES IN INORGANIC CHEMISTRY 1999. [DOI: 10.1016/s0898-8838(08)60082-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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75
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WOOLFOLK CA, WHITELEY HR. Reduction of inorganic compounds with molecular hydrogen by Micrococcus lactilyticus. I. Stoichiometry with compounds of arsenic, selenium, tellurium, transition and other elements. J Bacteriol 1998; 84:647-58. [PMID: 14001842 PMCID: PMC277940 DOI: 10.1128/jb.84.4.647-658.1962] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Woolfolk, C. A. (University of Washington, Seattle) and H. R. Whiteley. Reduction of inorganic compounds with molecular hydrogen by Micrococcus lactilyticus. I. Stoichiometry with compounds of arsenic, selenium, tellurium, transition and other elements. J. Bacteriol. 84:647-658. 1962.-Extracts of Micrococcus lactilyticus (Veillonella alcalescens) oxidize molecular hydrogen at the expense of certain compounds of arsenic, bismuth, selenium, tellurium, lead, thallium, vanadium, manganese, iron, copper, molybdenum, tungsten, osmium, ruthenium, gold, silver, and uranium, as well as molecular oxygen. Chemical and manometric data indicate that the following reductions are essentially quantitative: arsenate to arsenite, pentavalent and trivalent bismuth to the free element, selenite via elemental selenium to selenide, tellurate and tellurite to tellurium, lead dioxide and manganese dioxide to the divalent state, ferric to ferrous iron, osmium tetroxide to osmate ion, osmium dioxide and trivalent osmium to the metal, uranyl uranium to the tetravalent state, vanadate to the level of vanadyl, and polymolybdate ions to molybdenum blues with an average valence for molybdenum of +5. The results of a study of certain other hydrogenase-containing bacteria with respect to their ability to carry out some of the same reactions are also presented.
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76
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WHITELEY HR, WOOLFOLK CA. Ferredoxin-dependent reactions in Micrococcus lactilyticus. Biochem Biophys Res Commun 1998; 9:517-22. [PMID: 14000381 DOI: 10.1016/0006-291x(62)90118-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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77
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WHATLEY FR, TAGAWA K, ARNON DI. Separation of the light and dark reactions in electron transfer during photosynthesis. Proc Natl Acad Sci U S A 1998; 49:266-70. [PMID: 14000214 PMCID: PMC299795 DOI: 10.1073/pnas.49.2.266] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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78
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BUCHANAN BB, LOVENBERG W, RABINOWITZ JC. A comparison of clostridial ferredoxins. Proc Natl Acad Sci U S A 1998; 49:345-53. [PMID: 14016486 PMCID: PMC299830 DOI: 10.1073/pnas.49.3.345] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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79
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TAGAWA K, ARNON DI. Ferredoxins as electron carriers in photosynthesis and in the biological production and consumption of hydrogen gas. Nature 1998; 195:537-43. [PMID: 14039612 DOI: 10.1038/195537a0] [Citation(s) in RCA: 569] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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80
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Sticht H, Rösch P. The structure of iron-sulfur proteins. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 1998; 70:95-136. [PMID: 9785959 DOI: 10.1016/s0079-6107(98)00027-3] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Ferredoxins are a group of iron-sulfur proteins for which a wealth of structural and mutational data have recently become available. Previously unknown structures of ferredoxins which are adapted to halophilic, acidophilic or hyperthermophilic environments and new cysteine patterns for cluster ligation and non-cysteine cluster ligation have been described. Site-directed mutagenesis experiments have given insight into factors that influence the geometry, stability, redox potential, electronic properties and electron-transfer reactivity of iron-sulfur clusters.
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Affiliation(s)
- H Sticht
- Lehrstuhl für Struktur und Chemie der Biopolymere, Universität Bayreuth, Germany.
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81
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Abstract
Iron-sulfur proteins are found in all life forms. Most frequently, they contain Fe2S2, Fe3S4, and Fe4S4 clusters. These modular clusters undergo oxidation-reduction reactions, may be inserted or removed from proteins, can influence protein structure by preferential side chain ligation, and can be interconverted. In addition to their electron transfer function, iron-sulfur clusters act as catalytic centers and sensors of iron and oxygen. Their most common oxidation states are paramagnetic and present significant challenges for understanding the magnetic properties of mixed valence systems. Iron-sulfur clusters now rank with such biological prosthetic groups as hemes and flavins in pervasive occurrence and multiplicity of function.
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Affiliation(s)
- H Beinert
- Institute for Enzyme Research and the Department of Biochemistry, University of Wisconsin, Madison, WI 53705, USA
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82
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Iwasaki T, Suzuki T, Kon T, Imai T, Urushiyama A, Ohmori D, Oshima T. Novel zinc-containing ferredoxin family in thermoacidophilic archaea. J Biol Chem 1997; 272:3453-8. [PMID: 9013590 DOI: 10.1074/jbc.272.6.3453] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The dicluster-type ferredoxins from the thermoacidophilic archaea such as Thermoplasma acidophilum and Sulfolobus sp. are known to contain an unusually long extension of unknown function in the N-terminal region. Recent x-ray structural analysis of the Sulfolobus ferredoxin has revealed the presence of a novel zinc center, which is coordinated by three histidine ligand residues in the N-terminal region and one aspartate in the ferredoxin core domain. We report here the quantitative metal analyses together with electron paramagnetic resonance and resonance Raman spectra of T. acidophilum ferredoxin, demonstrating the presence of a novel zinc center in addition to one [3Fe-4S] and one [4Fe-4S] cluster (Fe/Zn = 6.8 mol/mol). A phylogenetic tree constructed for several archaeal monocluster and dicluster type ferredoxins suggests that the zinc-containing ferredoxins of T. acidophilum and Sulfolobus sp. form an independent subgroup, which is more distantly related to the ferredoxins from the hyperthermophiles than those from the methanogenic archaea, indicating the existence of a novel group of ferredoxins, namely, a "zinc-containing ferredoxin family" in the thermoacidophilic archaea. Inspection of the N-terminal extension regions of the archaeal zinc-containing ferredoxins suggested strict conservation of three histidine and one aspartate residues as possible ligands to the novel zinc center.
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Affiliation(s)
- T Iwasaki
- Department of Biochemistry and Molecular Biology, Nippon Medical School, Sendagi, Bunkyo-ku, Tokyo 113, Japan
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83
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Abstract
Otto Warburg died on 1 August 1970, after a very short illness. In the course of a career devoted entirely to research and extending over 60 years he made an exceptionally large number of highly original and far-reaching contributions to cell biology and biochemistry. In an age which has produced many outstanding scientists, he stands out as one of the great pioneers of contemporary biology. Lewis and Randall (31)*, in the preface to their
Thermodynamics
, liken the edifice of science to a cathedral built by the efforts of a few architects and many workers. In this sense Warburg belongs to the small band of real architects of his generation. He was born on 8 October 1883, in Freiburg im Breisgau where his father, Emil Warburg, was at that time Professor of Physics at the University. Emil Warburg (1846-1931) was one of the leading physicists of his time who made many classical contributions to his subject and formed a large school. An appreciation of his achievements and personality was published by James Franck (18), one of his students. * Figures given in round brackets refer to the list of references. Figures given in square brackets refer to the Bibliography.
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84
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NICHOLAS DJ. THE METABOLISM OF INORGANIC NITROGEN AND ITS COMPOUNDS IN MICRO-ORGANISMS. Biol Rev Camb Philos Soc 1996; 38:530-68. [PMID: 14058194 DOI: 10.1111/j.1469-185x.1963.tb00792.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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85
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Abstract
The formate oxidizing system of Methanobacillus omelianskii is specific for nicotinamide-adenine dinucleotide and requires ferredoxin, a biological carrier with the lowest known potential. ferredoxin from other obligate anaerobes is active in the reaction studied.
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86
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BLOMSTROM DC, KNIGHT E, PHILLIPS WD, WEIHER JF. THE NATURE OF IRON IN FERREDOXIN. Proc Natl Acad Sci U S A 1996; 51:1085-92. [PMID: 14215629 PMCID: PMC300217 DOI: 10.1073/pnas.51.6.1085] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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87
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CRESSWELL CF, HAGEMAN RH, HEWITT EJ, HUCKLESBY DP. THE REDUCTION OF NITRATE, NITRITE AND HYDROXYLAMINE TO AMMONIA BY ENZYMES FROM CUCURBITA PEPO L. IN THE PRESENCE OF REDUCED BENZYL VIOLOGEN AS ELECTRON DONOR. Biochem J 1996; 94:40-53. [PMID: 14342247 PMCID: PMC1206403 DOI: 10.1042/bj0940040] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
1. Enzyme systems from Cucurbita pepo have been shown to catalyse the reduction of nitrite and hydroxylamine to ammonia in yields about 90-100%. 2. Reduced benzyl viologen serves as an efficient electron donor for both systems. Activity of the nitrite-reductase system is directly related to degree of dye reduction when expressed in terms of the function for oxidation-reduction potentials, but appears to decrease to negligible activity below about 9% dye reduction. 3. NADH and NADPH alone produce negligible nitrite loss, but NADPH can be linked to an endogenous diaphorase system to reduce nitrite to ammonia in the presence of catalytic amounts of benzyl viologen. 4. The NADH- or NADPH-nitrate-reductase system that is also present can accept electrons from reduced benzyl viologen, but shows relationships opposite to that for the nitrite-reductase system with regard to effect of degree of dye reduction on activity. The product of nitrate reduction may be nitrite alone, or nitrite and ammonia, or ammonia alone, according only to the degree of dye reduction. 5. The relative activities of nitrite-reductase and hydroxylamine-reductase systems show different relationships with degree of dye reduction and may become reversed in magnitude when effects of degree of dye reduction are tested over a suitable range. 6. Nitrite severely inhibits the rate of reduction of hydroxylamine without affecting the yield of ammonia as a percentage of total substrate loss, but hydroxylamine has a negligible effect on the activity of the nitrite-reductase system. 7. The apparent K(m) for nitrite (1 mum) is substantially less than that for hydroxylamine, for which variable values between 0.05 and 0.9mm (mean 0.51 mm) have been observed. 8. The apparent K(m) values for reduced benzyl viologen differ for the nitrite-reductase and hydroxylamine-reductase systems: 60 and 7.5 mum respectively. 9. It is concluded that free hydroxylamine may not be an intermediate in the reduction of nitrite to ammonia by plants, and a possible mechanism for reduction of both compounds by the same enzyme system is discussed in the light of current ideas relating to other organisms.
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88
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JONES D, DEIBEL RH, NIVEN CF. CATALASE ACTIVITY OF TWO STREPTOCOCCUS FAECALIS STRAINS AND ITS ENHANCEMENT BY AEROBIOSIS AND ADDED CATIONS. J Bacteriol 1996; 88:602-10. [PMID: 14208495 PMCID: PMC277354 DOI: 10.1128/jb.88.3.602-610.1964] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Jones, Dorothy (American Meat Institute Foundation, Chicago, Ill.), R. H. Deibel, and C. F. Niven, Jr. Catalase activity of two Streptococcus faecalis strains and its enhancement by aerobiosis and added cations. J. Bacteriol. 88:602-610. 1964.-The nature of catalase activity noted in two unusual Streptococcus faecalis strains was determined. Enzyme activity was lost slowly when cultures were maintained by daily transfer in test tubes of broth media. Loss of activity could be prevented by aerobic culture. Supplementation of the growth medium with ferric, manganese, and zinc ions, as well as aerobiosis, enhanced catalase activity. However, addition of these cations to cell suspensions or to cell-free extracts did not increase catalase activity. Although oxygen was observed to be one of the reaction end products, the catalase activity was not inhibited by cyanide or azide, and the iron-porphyrin coenzyme of classical catalase was not detected. The enzyme was purified 185-fold by precipitation with ammonium sulfate, followed by chromotography on a diethylaminoethyl cellulose column.
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BACHOFEN R, BUCHANAN BB, ARNON DI. FERREDOXIN AS A REDUCTANT IN PYRUVATE SYNTHESIS BY A BACTERIAL EXTRACT. Proc Natl Acad Sci U S A 1996; 51:690-4. [PMID: 14166776 PMCID: PMC300141 DOI: 10.1073/pnas.51.4.690] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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ANDREW IG, MORRIS JG. THE BIOSYNTHESIS OF ALANINE BY CLOSTRIDIUM KLUYVERI. Biochim Biophys Acta Gen Subj 1996; 97:176-9. [PMID: 14284314 DOI: 10.1016/0304-4165(65)90292-8] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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91
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MORTENSON LE. FERREDOXIN REQUIREMENT FOR NITROGEN FIXATION BY EXTRACTS OF CLOSTRIDIUM PASTEURIANUM. ACTA ACUST UNITED AC 1996; 81:473-8. [PMID: 14170319 DOI: 10.1016/0926-6569(64)90132-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Abstract
Wilder, Martin (University of Kansas, Lawrence), R. C. Valentine, and J. M. Akagi. Ferredoxin of Clostridium thermosaccharolyticum. J. Bacteriol. 86:861-865. 1963.-An electron-transferring agent has been isolated from Clostridium thermosaccharolyticum. This factor was found to participate as an electron carrier in the phosphoroclastic reaction of pyruvate, with the subsequent formation of acetyl phosphate and molecular hydrogen. It can be employed interchangeably with the ferredoxin of C. pasteurianum in various reactions. Thermal-stability studies indicated that this factor from C. thermosaccharolyticum was comparatively more heat-resistant than the carrier obtained from C. pasteurianum. It was concluded that this carrier was ferredoxin or a ferredoxin-like substance.
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LOWE RH, EVANS HJ. PREPARATION AND SOME PROPERTIES OF A SOLUBLE NITRATE REDUCTASE FROM RHIZOBIUM JAPONICUM. ACTA ACUST UNITED AC 1996; 85:377-89. [PMID: 14194853 DOI: 10.1016/0926-6569(64)90301-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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NICHOLAS DJ, WILSON PJ. A DISSIMILATORY NITRATE REDUCTASE FROM NEUROSPORA CRASSA. Biochim Biophys Acta Gen Subj 1996; 86:466-76. [PMID: 14192898 DOI: 10.1016/0304-4165(64)90086-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Abstract
Valentine, R. C. (University of Illinois, Urbana) and R. S. Wolfe. Role of ferredoxin in the metabolism of molecular hydrogen. J. Bacteriol. 85:1114-1120. 1963.-The metabolism of molecular hydrogen by Clostridium pasteurianum, Micrococcus lactilyticus (Veillonella alcalescens), and several other anaerobic bacteria was studied. Oxidation of hydrogen, using several electron-accepting substrates including triphosphopyridine nucleotide, uric acid, xanthine, nitrite, and hydroxylamine, required ferredoxin in conjunction with hydrogenase. Evolution of hydrogen from pyruvate, alpha-ketoglutarate, hypoxanthine, and dithionite was mediated by ferredoxin. On the basis of these findings, a unitary hypothesis for biological hydrogen evolution is proposed in which ferredoxin plays a key role.
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TAGAWA K, TSUJIMOTO HY, ARNON DI. ANALYSIS OF PHOTOSYNTHETIC REACTIONS BY THE USE OF MONOCHROMATIC LIGHT. Nature 1996; 199:1247-52. [PMID: 14074585 DOI: 10.1038/1991247a0] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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97
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VALENTINE RC, BRILL WJ, SAGERS RD. FERREDOXIN LINKED DPN REDUCTION BY PYRUVATE IN EXTRACTS OF CLOSTRIDIUM ACIDI-URICI. Biochem Biophys Res Commun 1996; 12:315-9. [PMID: 14070336 DOI: 10.1016/0006-291x(63)90303-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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BUCHANAN BB, BACHOFEN R, ARNON DI. ROLE OF FERREDOXIN IN THE REDUCTIVE ASSIMILATION OF CO2 AND ACETATE BY EXTRACTS OF THE PHOTOSYNTHETIC BACTERIUM, CHROMATIUM. Proc Natl Acad Sci U S A 1996; 52:839-47. [PMID: 14212563 PMCID: PMC300355 DOI: 10.1073/pnas.52.3.839] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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