A radical intermediate in tyrosine scission to the CO and CN⁻ ligands of FeFe hydrogenase
The radical <em>S</em>-adenosylmethionine (SAM) enzyme HydG lyses free L-tyrosine to produce CO and CN<em><sup>−</sup></em> for the assembly of the catalytic H cluster of FeFe hydrogenase. We used electron paramagnetic resonance spectroscopy to detect and characte...
| Päätekijät: | , , , , , , |
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| Aineistotyyppi: | Journal article |
| Kieli: | English |
| Julkaistu: |
American Association for the Advancement of Science
2013
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| _version_ | 1826268114529026048 |
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| author | Kuchenreuther, J Myers, W Stich, T George, S NejatyJahromy, Y Swartz, JR Britt, R |
| author_facet | Kuchenreuther, J Myers, W Stich, T George, S NejatyJahromy, Y Swartz, JR Britt, R |
| author_sort | Kuchenreuther, J |
| collection | OXFORD |
| description | The radical <em>S</em>-adenosylmethionine (SAM) enzyme HydG lyses free L-tyrosine to produce CO and CN<em><sup>−</sup></em> for the assembly of the catalytic H cluster of FeFe hydrogenase. We used electron paramagnetic resonance spectroscopy to detect and characterize HydG reaction intermediates generated with a set of <sup>2</sup>H, <sup>13</sup>C, and <sup>15</sup>N nuclear spin-labeled tyrosine substrates. We propose a detailed reaction mechanism in which the radical SAM reaction, initiated at an N-terminal 4Fe-4S cluster, generates a tyrosine radical bound to a C-terminal 4Fe-4S cluster. Heterolytic cleavage of this tyrosine radical at the C<sub>α</sub>-C<sub>β</sub> bond forms a transient 4-oxidobenzyl (4OB<em><sup>•</sup></em>) radical and a dehydroglycine bound to the C-terminal 4Fe-4S cluster. Electron and proton transfer to this 4OB<em><sup>•</sup></em> radical forms <em>p</em>-cresol, with the conversion of this dehydroglycine ligand to Fe-bound CO and CN<em><sup>−</sup></em>, a key intermediate in the assembly of the 2Fe subunit of the H cluster. |
| first_indexed | 2024-03-06T21:04:38Z |
| format | Journal article |
| id | oxford-uuid:3c06b35b-9fd6-41a8-ae5d-97bb3a3adc98 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T21:04:38Z |
| publishDate | 2013 |
| publisher | American Association for the Advancement of Science |
| record_format | dspace |
| spelling | oxford-uuid:3c06b35b-9fd6-41a8-ae5d-97bb3a3adc982022-03-26T14:11:08ZA radical intermediate in tyrosine scission to the CO and CN⁻ ligands of FeFe hydrogenaseJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:3c06b35b-9fd6-41a8-ae5d-97bb3a3adc98EnglishSymplectic Elements at OxfordAmerican Association for the Advancement of Science2013Kuchenreuther, JMyers, WStich, TGeorge, SNejatyJahromy, YSwartz, JRBritt, RThe radical <em>S</em>-adenosylmethionine (SAM) enzyme HydG lyses free L-tyrosine to produce CO and CN<em><sup>−</sup></em> for the assembly of the catalytic H cluster of FeFe hydrogenase. We used electron paramagnetic resonance spectroscopy to detect and characterize HydG reaction intermediates generated with a set of <sup>2</sup>H, <sup>13</sup>C, and <sup>15</sup>N nuclear spin-labeled tyrosine substrates. We propose a detailed reaction mechanism in which the radical SAM reaction, initiated at an N-terminal 4Fe-4S cluster, generates a tyrosine radical bound to a C-terminal 4Fe-4S cluster. Heterolytic cleavage of this tyrosine radical at the C<sub>α</sub>-C<sub>β</sub> bond forms a transient 4-oxidobenzyl (4OB<em><sup>•</sup></em>) radical and a dehydroglycine bound to the C-terminal 4Fe-4S cluster. Electron and proton transfer to this 4OB<em><sup>•</sup></em> radical forms <em>p</em>-cresol, with the conversion of this dehydroglycine ligand to Fe-bound CO and CN<em><sup>−</sup></em>, a key intermediate in the assembly of the 2Fe subunit of the H cluster. |
| spellingShingle | Kuchenreuther, J Myers, W Stich, T George, S NejatyJahromy, Y Swartz, JR Britt, R A radical intermediate in tyrosine scission to the CO and CN⁻ ligands of FeFe hydrogenase |
| title | A radical intermediate in tyrosine scission to the CO and CN⁻ ligands of FeFe hydrogenase |
| title_full | A radical intermediate in tyrosine scission to the CO and CN⁻ ligands of FeFe hydrogenase |
| title_fullStr | A radical intermediate in tyrosine scission to the CO and CN⁻ ligands of FeFe hydrogenase |
| title_full_unstemmed | A radical intermediate in tyrosine scission to the CO and CN⁻ ligands of FeFe hydrogenase |
| title_short | A radical intermediate in tyrosine scission to the CO and CN⁻ ligands of FeFe hydrogenase |
| title_sort | radical intermediate in tyrosine scission to the co and cn⁻ ligands of fefe hydrogenase |
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