Electrochemical investigations of the interconversions between catalytic and inhibited states of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans.
Studies of the catalytic properties of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans by protein film voltammetry, under a H2 atmosphere, reveal and establish a variety of interesting properties not observed or measured quantitatively with other techniques. The catalytic bias (inherent abil...
| Main Authors: | , , , |
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| Format: | Journal article |
| Language: | English |
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2006
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| _version_ | 1826272201637101568 |
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| author | Parkin, A Cavazza, C Fontecilla-Camps, J Armstrong, F |
| author_facet | Parkin, A Cavazza, C Fontecilla-Camps, J Armstrong, F |
| author_sort | Parkin, A |
| collection | OXFORD |
| description | Studies of the catalytic properties of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans by protein film voltammetry, under a H2 atmosphere, reveal and establish a variety of interesting properties not observed or measured quantitatively with other techniques. The catalytic bias (inherent ability to oxidize hydrogen vs reduce protons) is quantified over a wide pH range: the enzyme is proficient at both H2 oxidation (from pH > 6) and H2 production (pH < 6). Hydrogen production is inhibited by H2, but the effect is much smaller than observed for [NiFe]-hydrogenases from Allochromatium vinosum or Desulfovibrio fructosovorans. Under anaerobic conditions and positive potentials, the [FeFe]-hydrogenase is oxidized to an inactive form, inert toward reaction with CO and O2, that rapidly reactivates upon one-electron reduction under 1 bar of H2. The potential dependence of this interconversion shows that the oxidized inactive form exists in two pH-interconvertible states with pK(ox) = 5.9. Studies of the CO-inhibited enzyme under H2 reveals a strong enhancement of the rate of activation by white light at -109 mV (monitoring H2 oxidation) that is absent at low potential (-540 mV, monitoring H+ reduction), thus demonstrating photolability that is dependent upon the oxidation state. |
| first_indexed | 2024-03-06T22:08:48Z |
| format | Journal article |
| id | oxford-uuid:5116cf22-5967-4ef0-b514-6e9e2a472109 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T22:08:48Z |
| publishDate | 2006 |
| record_format | dspace |
| spelling | oxford-uuid:5116cf22-5967-4ef0-b514-6e9e2a4721092022-03-26T16:17:22ZElectrochemical investigations of the interconversions between catalytic and inhibited states of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:5116cf22-5967-4ef0-b514-6e9e2a472109EnglishSymplectic Elements at Oxford2006Parkin, ACavazza, CFontecilla-Camps, JArmstrong, FStudies of the catalytic properties of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans by protein film voltammetry, under a H2 atmosphere, reveal and establish a variety of interesting properties not observed or measured quantitatively with other techniques. The catalytic bias (inherent ability to oxidize hydrogen vs reduce protons) is quantified over a wide pH range: the enzyme is proficient at both H2 oxidation (from pH > 6) and H2 production (pH < 6). Hydrogen production is inhibited by H2, but the effect is much smaller than observed for [NiFe]-hydrogenases from Allochromatium vinosum or Desulfovibrio fructosovorans. Under anaerobic conditions and positive potentials, the [FeFe]-hydrogenase is oxidized to an inactive form, inert toward reaction with CO and O2, that rapidly reactivates upon one-electron reduction under 1 bar of H2. The potential dependence of this interconversion shows that the oxidized inactive form exists in two pH-interconvertible states with pK(ox) = 5.9. Studies of the CO-inhibited enzyme under H2 reveals a strong enhancement of the rate of activation by white light at -109 mV (monitoring H2 oxidation) that is absent at low potential (-540 mV, monitoring H+ reduction), thus demonstrating photolability that is dependent upon the oxidation state. |
| spellingShingle | Parkin, A Cavazza, C Fontecilla-Camps, J Armstrong, F Electrochemical investigations of the interconversions between catalytic and inhibited states of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans. |
| title | Electrochemical investigations of the interconversions between catalytic and inhibited states of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans. |
| title_full | Electrochemical investigations of the interconversions between catalytic and inhibited states of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans. |
| title_fullStr | Electrochemical investigations of the interconversions between catalytic and inhibited states of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans. |
| title_full_unstemmed | Electrochemical investigations of the interconversions between catalytic and inhibited states of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans. |
| title_short | Electrochemical investigations of the interconversions between catalytic and inhibited states of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans. |
| title_sort | electrochemical investigations of the interconversions between catalytic and inhibited states of the fefe hydrogenase from desulfovibrio desulfuricans |
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