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Hélène Marie Jouve - One of the best experts on this subject based on the ideXlab platform.
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Spectroscopic description of an unusual protonated ferryl species in the Catalase from Proteus mirabilis and density functional theory calculations on related models. Consequences for the ferryl protonation state in Catalase, peroxidase and chloroper
JBIC, 2007Co-Authors: Olivier Horner, Jean-marie Mouesca, P. L. Solari, M. Orio, J.-l. Oddou, P. Bonville, Hélène Marie JouveAbstract:The Catalase from Proteus mirabilis peroxide-resistant bacteria is one of the most efficient heme-containing Catalases. It forms a relatively stable compound II. We were able to prepare samples of compound II from P. mirabilis Catalase enriched in 57Fe and to study them by spectroscopic methods. Two different forms of compound II, namely, low-pH compound II (LpH II) and high-pH compound II (HpH II), have been characterized by Mössbauer, extended X-ray absorption fine structure (EXAFS) and UV-vis absorption spectroscopies. The proportions of the two forms are pH-dependent and the pH conversion between HpH II and LpH II is irreversible. Considering (1) the Mössbauer parameters evaluated for four related models by density functional theory methods, (2) the existence of two different Fe–Oferryl bond lengths (1.80 and 1.66 Å) compatible with our EXAFS data and (3) the pH dependence of the α band to β band intensity ratio in the absorption spectra, we attribute the LpH II compound to a protonated ferryl FeIV–OH complex (Fe–O approximately 1.80 Å), whereas the HpH II compound corresponds to the classic ferryl FeIV=O complex (Fe=O approximately 1.66 Å). The large quadrupole splitting value of LpH II (measured 2.29 mm s−1 vs. computed 2.15 mm s−1) compared with that of HpH II (measured 1.47 mm s−1 vs. computed 1.46 mm s−1) reflects the protonation of the ferryl group. The relevancy and involvement of such (FeIV=O/FeIV–OH) species in the reactivity of Catalase, peroxidase and chloroperoxidase are discussed.
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Cold adapted features of Vibrio salmonicida Catalase: characterisation and comparison to the mesophilic counterpart from Proteus mirabilis
Extremophiles, 2006Co-Authors: Marit Sjo Lorentzen, Hélène Marie Jouve, Nils Peder WillassenAbstract:The gene encoding Catalase from the psychrophilic marine bacterium Vibrio salmonicida LFI1238 was identified, cloned and expressed in the Catalase-deficient Escherichia coli UM2. Recombinant Catalase from V. salmonicida (VSC) was purified to apparent homogeneity as a tetramer with a molecular mass of 235 kDa. VSC contained 67% heme b and 25% protoporphyrin IX. VSC was able to bind NADPH, react with cyanide and form compounds I and II as other monofunctional small subunit heme Catalases. Amino acid sequence alignment of VSC and Catalase from the mesophilic Proteus mirabilis (PMC) revealed 71% identity. As for cold adapted enzymes in general, VSC possessed a lower temperature optimum and higher catalytic efficiency ( k _cat/ K _m) compared to PMC. VSC have higher affinity for hydrogen peroxide (apparent K _m) at all temperatures. For VSC the turnover rate ( k _cat) is slightly lower while the catalytic efficiency is slightly higher compared to PMC over the temperature range measured, except at 4°C. Moreover, the catalytic efficiency of VSC and PMC is almost temperature independent, except at 4°C where PMC has a twofold lower efficiency compared to VSC. This may indicate that VSC has evolved to maintain a high efficiency at low temperatures.
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High-resolution structure and biochemical properties of a recombinant Proteus mirabilis Catalase depleted in iron.
Proteins - Structure Function and Bioinformatics, 2003Co-Authors: Pierre Andreoletti, Jean Gagnon, Germaine Sainz, Michel Jaquinod, Hélène Marie JouveAbstract:Heme Catalases are homotetrameric enzymes with a highly conserved complex quaternary structure, and their functional role is still not well understood. Proteus mirabilis Catalase (PMC), a heme enzyme belonging to the family of NADPH-binding Catalases, was efficiently overexpressed in E. coli. The recombinant Catalase (rec PMC) was deficient in heme with one-third heme and two-thirds protoporphyrin IX as determined by mass spectrometry and chemical methods. This ratio was influenced by the expression conditions, but the enzyme-specific activity calculated relative to the heme content remained unchanged. The crystal structure of rec PMC was solved to a resolution of 2.0 A, the highest resolution obtained to date with PMC. The overall structure was quite similar to that of wild-type PMC, and it is surprising that the absence of iron had no effect on the structure of the active site. Met 53 close to the essential His 54 was found less oxidized in rec PMC than in the wild-type enzyme. An acetate anion was modeled in an anionic pocket, away from the heme group but important for the enzymatic reaction. An alternate conformation observed for Arg 99 could play a role in the formation of the H-bond network connecting two symmetrical subunits of the tetramer.
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Structure of Catalases
Cold Spring Harbor Monograph Archive, 1997Co-Authors: Jerónimo Bravo, Hélène Marie Jouve, Ignacio Fita, P. Gouet, W.r. Melik-adamyan, Garib N. MurshudovAbstract:Catalase (hydrogen peroxide: hydrogen peroxide oxidoreductase, EC 1.11.1.6) is found in virtually all aerobic organisms. It employs a two-electron-transfer mechanism to disproportionate hydrogen peroxide into molecular oxygen and water (Deisseroth and Dounce 1970). These enzymes serve, in part, to protect the cell from the toxic effects of small peroxides. However, the entire range of biological functions of Catalases remains unclear. Two types of Catalases are known: Mn-Catalases and heme-containing Catalases. Mn-Catalases, only present in certain prokaryotes, are non-heme hexameric enzymes with an “all-α” fold (Barynin et al. 1986). In contrast, heme-containing Catalases, which are widespread, are homotetramers with molecular weights ranging from about 200,000 to 350,000. The three-dimensional crystal structures of five of these heme-containing Catalases (Table 1) have been reported at almost atomic resolution. These include members from two eukaryote and from three prokaryote Catalases: (1) from the fungus Penicillium vitale (PVC) (Vainshtein et al. 1981Vainshtein et al. 1986; G. Murshudov et al., unpubl.); (2) the mammalian Catalase from beef liver (BLC) (Murthy et al. 1981; Fita et al. 1986); (3) from Micrococcus lysodeikticus (MLC) (Murshudov et al. 1992 and unpubl.), (4) from a peroxide-resistant mutant of Proteus mirabilis (PMC_PR) (Gouet et al. 1995); and (5) HPII Catalase from E. coli (Bravo et al. 1995). The α+β fold of the subunits and the molecular organization in all these heme Catalase structures are unique among proteins and, in particular, present striking differences from heme peroxidases. In Catalases the four heme groups are deeply buried inside the molecule due to complex intersubunit interactions...
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Ferryl intermediates of Catalase captured by time-resolved Weissenberg crystallography and UV-VIS spectroscopy
Nature Structural Biology, 1996Co-Authors: Patrice Gouet, Hélène Marie Jouve, I. Andersson, L. Nussaume, Pierre Andreoletti, Pamela A. Williams, J. HajduAbstract:Various enzymes use semi-stable ferryl intermediates and free radicals during their catalytic cycle, amongst them haem Catalases. Structures for two transient intermediates (compounds I and II) of the NADPH-dependent Catalase from Proteus mirabilis (PMC) have been determined by time-resolved X-ray crystallography and single crystal microspectrophotometry. The results show the formation and transformation of the ferryl group in the haem, and the unexpected binding of an anion during this reaction at a site distant from the haem.
Pierre Andreoletti - One of the best experts on this subject based on the ideXlab platform.
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High-resolution structure and biochemical properties of a recombinant Proteus mirabilis Catalase depleted in iron.
Proteins - Structure Function and Bioinformatics, 2003Co-Authors: Pierre Andreoletti, Jean Gagnon, Germaine Sainz, Michel Jaquinod, Hélène Marie JouveAbstract:Heme Catalases are homotetrameric enzymes with a highly conserved complex quaternary structure, and their functional role is still not well understood. Proteus mirabilis Catalase (PMC), a heme enzyme belonging to the family of NADPH-binding Catalases, was efficiently overexpressed in E. coli. The recombinant Catalase (rec PMC) was deficient in heme with one-third heme and two-thirds protoporphyrin IX as determined by mass spectrometry and chemical methods. This ratio was influenced by the expression conditions, but the enzyme-specific activity calculated relative to the heme content remained unchanged. The crystal structure of rec PMC was solved to a resolution of 2.0 A, the highest resolution obtained to date with PMC. The overall structure was quite similar to that of wild-type PMC, and it is surprising that the absence of iron had no effect on the structure of the active site. Met 53 close to the essential His 54 was found less oxidized in rec PMC than in the wild-type enzyme. An acetate anion was modeled in an anionic pocket, away from the heme group but important for the enzymatic reaction. An alternate conformation observed for Arg 99 could play a role in the formation of the H-bond network connecting two symmetrical subunits of the tetramer.
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Ferryl intermediates of Catalase captured by time-resolved Weissenberg crystallography and UV-VIS spectroscopy
Nature Structural Biology, 1996Co-Authors: Patrice Gouet, Hélène Marie Jouve, I. Andersson, L. Nussaume, Pierre Andreoletti, Pamela A. Williams, J. HajduAbstract:Various enzymes use semi-stable ferryl intermediates and free radicals during their catalytic cycle, amongst them haem Catalases. Structures for two transient intermediates (compounds I and II) of the NADPH-dependent Catalase from Proteus mirabilis (PMC) have been determined by time-resolved X-ray crystallography and single crystal microspectrophotometry. The results show the formation and transformation of the ferryl group in the haem, and the unexpected binding of an anion during this reaction at a site distant from the haem.
J. Hajdu - One of the best experts on this subject based on the ideXlab platform.
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Ferryl intermediates of Catalase captured by time-resolved Weissenberg crystallography and UV-VIS spectroscopy
Nature Structural Biology, 1996Co-Authors: Patrice Gouet, Hélène Marie Jouve, I. Andersson, L. Nussaume, Pierre Andreoletti, Pamela A. Williams, J. HajduAbstract:Various enzymes use semi-stable ferryl intermediates and free radicals during their catalytic cycle, amongst them haem Catalases. Structures for two transient intermediates (compounds I and II) of the NADPH-dependent Catalase from Proteus mirabilis (PMC) have been determined by time-resolved X-ray crystallography and single crystal microspectrophotometry. The results show the formation and transformation of the ferryl group in the haem, and the unexpected binding of an anion during this reaction at a site distant from the haem.
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Ferryl intermediates of Catalase captured by time-resolved Weissenberg crystallography and UV-VIS spectroscopy.
Nat Struct Biol, 1996Co-Authors: P. Gouet, Hm Jouve, Pa Williams, I. Andersson, P. Andreoletti, L. Nussaume, J. HajduAbstract:Various enzymes use semi-stable ferryl intermediates and free radicals during their catalytic cycle, amongst them haem Catalases. Structures for two transient intermediates (compounds I and II) of the NADPH-dependent Catalase from Proteus mirabilis (PMC) have been determined by time-resolved X-ray crystallography and single crystal microspectrophotometry. The results show the formation and transformation of the ferryl group in the haem, and the unexpected binding of an anion during this reaction at a site distant from the haem.Various enzymes use semi-stable ferryl intermediates and free radicals during their catalytic cycle, amongst them haem Catalases. Structures for two transient intermediates (compounds I and II) of the NADPH-dependent Catalase from Proteus mirabilis (PMC) have been determined by time-resolved X-ray crystallography and single crystal microspectrophotometry. The results show the formation and transformation of the ferryl group in the haem, and the unexpected binding of an anion during this reaction at a site distant from the haem.
Karl D Straub - One of the best experts on this subject based on the ideXlab platform.
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Catalase as a sulfide-sulfur oxido-reductase: An ancient (and modern?) regulator of reactive sulfur species (RSS)
Redox Biology, 2017Co-Authors: Kenneth R Olson, Faihaan Arif, Maaz Arif, Nitin Arora, Eric R Deleon, Yan Gao, Karl D StraubAbstract:Catalase is well-known as an antioxidant dismutating H2O2 to O2 and H2O. However, Catalases evolved when metabolism was largely sulfur-based, long before O2 and reactive oxygen species (ROS) became abundant, suggesting Catalase metabolizes reactive sulfide species (RSS). Here we examine Catalase metabolism of H2Sn, the sulfur analog of H2O2, hydrogen sulfide (H2S) and other sulfur-bearing molecules using H2S-specific amperometric electrodes and fluorophores to measure polysulfides (H2Sn; SSP4) and ROS (dichlorofluorescein, DCF). Catalase eliminated H2Sn, but did not anaerobically generate H2S, the expected product of dismutation. Instead, Catalase concentration- and oxygen-dependently metabolized H2S and in so doing acted as a sulfide oxidase with a P50 of 20 mmHg. H2O2 had little effect on Catalase-mediated H2S metabolism but in the presence of the Catalase inhibitor, sodium azide (Az), H2O2 rapidly and efficiently expedited H2S metabolism in both normoxia and hypoxia suggesting H2O2 is an effective electron acceptor in this reaction. Unexpectedly, Catalase concentration-dependently generated H2S from dithiothreitol (DTT) in both normoxia and hypoxia, concomitantly oxidizing H2S in the presence of O2. H2S production from DTT was inhibited by carbon monoxide and augmented by NADPH suggesting that Catalase heme-iron is the catalytic site and that NADPH provides reducing equivalents. Catalase also generated H2S from garlic oil, diallyltrisulfide, thioredoxin and sulfur dioxide, but not from sulfite, metabisulfite, carbonyl sulfide, cysteine, cystine, glutathione or oxidized glutathione. Oxidase activity was also present in Catalase from Aspergillus niger. These results show that Catalase can act as either a sulfide oxidase or sulfur reductase and they suggest that these activities likely played a prominent role in sulfur metabolism during evolution and may continue do so in modern cells as well. This also appears to be the first observation of Catalase reductase activity independent of peroxide dismutation.
Paula Ludovico - One of the best experts on this subject based on the ideXlab platform.
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caloric restriction or Catalase inactivation extends yeast chronological lifespan by inducing h2o2 and superoxide dismutase activity
Proceedings of the National Academy of Sciences of the United States of America, 2010Co-Authors: Ana Mesquita, Martin Weinberger, Alexandra Silva, Belem Sampaiomarques, Bruno Almeida, Cecilia Leao, Vitor Costa, Fernando Rodrigues, William C Burhans, Paula LudovicoAbstract:The free radical theory of aging posits oxidative damage to macromolecules as a primary determinant of lifespan. Recent studies challenge this theory by demonstrating that in some cases, longevity is enhanced by inactivation of oxidative stress defenses or is correlated with increased, rather than decreased reactive oxygen species and oxidative damage. Here we show that, in Saccharomyces cerevisiae, caloric restriction or inactivation of Catalases extends chronological lifespan by inducing elevated levels of the reactive oxygen species hydrogen peroxide, which activate superoxide dismutases that inhibit the accumulation of superoxide anions. Increased hydrogen peroxide in Catalase-deficient cells extends chronological lifespan despite parallel increases in oxidative damage. These findings establish a role for hormesis effects of hydrogen peroxide in promoting longevity that have broad implications for understanding aging and age-related diseases.
