FTIR study on the light sensitivity of the [NiFe] hydrogenase from Desulfovibrio vulgaris Miyazaki F: Ni–C to Ni–L photoconversion, kinetics of proton rebinding and H/D isotope effect

Kellers, Petra; Pandelia, Maria-Eirini; Currell, Leslie J.; Görner, Helmut; Lubitz, Wolfgang

doi:10.1039/b913635e

Cited by 35 publications

(52 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…100 cm −1 as observed for [(dppe)Pt(pdt)Fe(CO) 3 ] +/0 , a Pt II Fe I /Pt II Fe 0 couple. 21 For the Ni-L state of the [NiFe]-hydrogenases, the values of ν̃ CO range from 1911 ( Desulfovibrio vulgaris Miyazaki F) 34 to 1862 cm −1 ( Aquifex aeolicus ) (Table 4). 26,35 …”

Section: Resultsmentioning

confidence: 99%

Models of the Ni-L and Ni-SI_a States of the [NiFe]-Hydrogenase Active Site

Chambers

Huynh

et al. 2015

Inorg. Chem.

Self Cite

View full text Add to dashboard Cite

A new class of synthetic models for the active site of [NiFe]-hydrogenases are described. The NiI/II(SCys)2 and FeII(CN)2CO sites are represented with (RC5H4)NiI/II and FeII(diphos)(CO) modules, where diphos = 1,2-C2H4(PPh2)2(dppe) or cis-1,2-C2H2(PPh2)2(dppv). The two bridging thiolate ligands are represented by CH2(CH2S)22− (pdt2−), Me2C(CH2S)22− (Me2pdt2−), and (C6H5S)22−. The reaction of Fe(pdt)(CO)2(dppe) and [(C5H5)3Ni2]BF4 affords [(C5H5)Ni(pdt)Fe(dppe)-(CO)]BF4 ([1a]BF4). Monocarbonyl [1a]BF4 features an S = 0 NiIIFeII center with five-coordinated iron, as proposed for the Ni-SIa state of the enzyme. One-electron reduction of [1a]+ affords the S = 1/2 derivative [1a]0, which, according to density functional theory (DFT) calculations and electron paramagnetic resonance and Mössbauer spectroscopies, is best described as a NiIFeII compound. The NiIFeII assignment matches that for the Ni-L state in [NiFe]-hydrogenase, unlike recently reported NiIIFeI-based models. Compound [1a]0 reacts with strong acids to liberate 0.5 equiv of H2 and regenerate [1a]+, indicating that H2 evolution is catalyzed by [1a]0. DFT calculations were used to investigate the pathway for H2 evolution and revealed that the mechanism can proceed through two isomers of [1a]0 that differ in the stereochemistry of the Fe(dppe)CO center. Calculations suggest that protonation of [1a]0 (both isomers) affords NiIII–H–FeII intermediates, which represent mimics of the Ni-C state of the enzyme.

show abstract

Section: Resultsmentioning

confidence: 99%

Models of the Ni-L and Ni-SI_a States of the [NiFe]-Hydrogenase Active Site

Chambers

Huynh

et al. 2015

Inorg. Chem.

Self Cite

View full text Add to dashboard Cite

show abstract

“…A light-minus-dark FTIR difference spectrum for the D. vulgaris MF hydrogenase is shown in Figure 6 c. Rapid scan kinetic measurements (Figure 7 a) showed that rebinding of the hydride ligand as a proton is a first-order process. [124] The determined activation barrier is 46 kJ mol…”

Section: Light-induced Structural Changes In the Active Sitementioning

confidence: 99%

Intermediates in the Catalytic Cycle of [NiFe] Hydrogenase: Functional Spectroscopy of the Active Site

2010

Self Cite

View full text Add to dashboard Cite

The [NiFe] hydrogenase from the anaerobic sulphate reducing bacterium Desulfovibrio vulgaris Miyazaki F is an excellent model for constructing a mechanism for the function of the so-called 'oxygen-sensitive' hydrogenases. The present review focuses on spectroscopic investigations of the active site intermediates playing a role in the activation/deactivation and catalytic cycle of this enzyme as well as in the inhibition by carbon monoxide or molecular oxygen and the light-sensitivity of the hydrogenase. The methods employed include magnetic resonance and vibrational (FTIR) techniques combined with electrochemistry that deliver information about details of the geometrical and electronic structure of the intermediates and their redox behaviour. Based on these data a mechanistic scheme is developed.

show abstract

“…In this case, the Ni-Fe bond would be present transiently, because the state containing this bond would be generated in aqueous solvent where [H + ] is ~ 10 −7 M, such that the rate of protonation may be exceedingly fast. Interestingly, the Ni-L state of the enzyme, obtained by exposing frozen solutions in the Ni-C state to light, may contain the Ni I -Fe II bond after the bridging proton dissociates [37]. Perhaps during catalysis, Ni-L may form transiently, converting rapidly to Ni-C upon protonation (Figure 3, bottom).…”

Section: 4 Evidence For M-m Bonds In Metalloenzymesmentioning

confidence: 99%

Metal–metal bonds in biology

Lindahl

2012

Journal of Inorganic Biochemistry

View full text Add to dashboard Cite

Nickel-containing carbon monoxide dehydrogenases, acetyl-CoA synthases, nickel-iron hydrogenases, and diron hydrogenases are distinct metalloenzymes yet they share a number of important characteristics. All are O2-sensitive, with active-sites composed of iron and/or nickel ions coordinated primarily by sulfur ligands. In each case, two metals are juxtaposed at the “heart” of the active site, within range of forming metal-metal bonds. These active-site clusters exhibit multielectron redox abilities and must be reductively activated for catalysis. Reduction potentials are milder than expected based on formal oxidation state changes. When reductively activated, each cluster attacks an electrophilic substrate via an oxidative addition reaction. This affords a two-electron-reduced substrate bound to one or both metals of an oxidized cluster. M-M bonds have been established in hydrogenases where they serve to initiate the oxidative addition of protons and perhaps stabilize active sites in multiple redox states. The same may be true of the CODH and ACS active sites – Ni-Fe and Ni-Ni bonds in these sites may play critical roles in catalysis, stabilizing low-valence states and initiating oxidative addition of CO2 and methyl group cations, respectively. In this article, the structural and functional commonalities of these metalloenzyme active sites are described, and the case is made for the formation and use of metal-metal bonds in each enzyme mentioned. As a post-script, the importance of Fe-Fe bonds in the nitrogenase FeMoco active site is discussed.

show abstract

FTIR study on the light sensitivity of the [NiFe] hydrogenase from Desulfovibrio vulgaris Miyazaki F: Ni–C to Ni–L photoconversion, kinetics of proton rebinding and H/D isotope effect

Cited by 35 publications

References 20 publications

Models of the Ni-L and Ni-SI_a States of the [NiFe]-Hydrogenase Active Site

Models of the Ni-L and Ni-SI_a States of the [NiFe]-Hydrogenase Active Site

Intermediates in the Catalytic Cycle of [NiFe] Hydrogenase: Functional Spectroscopy of the Active Site

Metal–metal bonds in biology

Contact Info

Product

Resources

About

FTIR study on the light sensitivity of the [NiFe] hydrogenase from Desulfovibrio vulgaris Miyazaki F: Ni–C to Ni–L photoconversion, kinetics of proton rebinding and H/D isotope effect

Cited by 35 publications

References 20 publications

Models of the Ni-L and Ni-SIa States of the [NiFe]-Hydrogenase Active Site

Models of the Ni-L and Ni-SIa States of the [NiFe]-Hydrogenase Active Site

Intermediates in the Catalytic Cycle of [NiFe] Hydrogenase: Functional Spectroscopy of the Active Site

Metal–metal bonds in biology

Contact Info

Product

Resources

About

Models of the Ni-L and Ni-SI_a States of the [NiFe]-Hydrogenase Active Site

Models of the Ni-L and Ni-SI_a States of the [NiFe]-Hydrogenase Active Site