Shanika Yadav, Rieke Haas, Esma Birsen Boydas, Michael Roemelt, Thomas Happe, Ulf-Peter Apfel and Sven T. Stripp
{"title":"FeFe]-氢化酶的氧敏感性:酶内与酶外活性位点模拟物的比较研究","authors":"Shanika Yadav, Rieke Haas, Esma Birsen Boydas, Michael Roemelt, Thomas Happe, Ulf-Peter Apfel and Sven T. Stripp","doi":"10.1039/D3CP06048A","DOIUrl":null,"url":null,"abstract":"<p >[FeFe]-hydrogenase is nature's most efficient proton reducing and H<small><sub>2</sub></small>-oxidizing enzyme. However, biotechnological applications are hampered by the O<small><sub>2</sub></small> sensitivity of this metalloenzyme, and the mechanism of aerobic deactivation is not well understood. Here, we explore the oxygen sensitivity of four mimics of the organometallic active site cofactor of [FeFe]-hydrogenase, [Fe<small><sub>2</sub></small>(adt)(CO)<small><sub>6−<em>x</em></sub></small>(CN)<small><sub><em>x</em></sub></small>]<small><sup><em>x</em>−</sup></small> and [Fe<small><sub>2</sub></small>(pdt)(CO)<small><sub>6−<em>x</em></sub></small>(CN)<small><sub><em>x</em></sub></small>]<small><sup><em>x</em>−</sup></small> (<em>x</em> = 1, 2) as well as the corresponding cofactor variants of the enzyme by means of infrared, Mössbauer, and NMR spectroscopy. Additionally, we describe a straightforward synthetic recipe for the active site precursor complex Fe<small><sub>2</sub></small>(adt)(CO)<small><sub>6</sub></small>. Our data indicate that the aminodithiolate (adt) complex, which is the synthetic precursor of the natural active site cofactor, is most oxygen sensitive. This observation highlights the significance of proton transfer in aerobic deactivation, and supported by DFT calculations facilitates an identification of the responsible reactive oxygen species (ROS). Moreover, we show that the ligand environment of the iron ions critically influences the reactivity with O<small><sub>2</sub></small> and ROS like superoxide and H<small><sub>2</sub></small>O<small><sub>2</sub></small> as the oxygen sensitivity increases with the exchange of ligands from CO to CN<small><sup>−</sup></small>. The trends in aerobic deactivation observed for the model complexes are in line with the respective enzyme variants. Based on experimental and computational data, a model for the initial reaction of [FeFe]-hydrogenase with O<small><sub>2</sub></small> is developed. Our study underscores the relevance of model systems in understanding biocatalysis and validates their potential as important tools for elucidating the chemistry of oxygen-induced deactivation of [FeFe]-hydrogenase.</p>","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":" 28","pages":" 19105-19116"},"PeriodicalIF":2.9000,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/cp/d3cp06048a?page=search","citationCount":"0","resultStr":"{\"title\":\"Oxygen sensitivity of [FeFe]-hydrogenase: a comparative study of active site mimics inside vs. outside the enzyme†\",\"authors\":\"Shanika Yadav, Rieke Haas, Esma Birsen Boydas, Michael Roemelt, Thomas Happe, Ulf-Peter Apfel and Sven T. Stripp\",\"doi\":\"10.1039/D3CP06048A\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p >[FeFe]-hydrogenase is nature's most efficient proton reducing and H<small><sub>2</sub></small>-oxidizing enzyme. However, biotechnological applications are hampered by the O<small><sub>2</sub></small> sensitivity of this metalloenzyme, and the mechanism of aerobic deactivation is not well understood. Here, we explore the oxygen sensitivity of four mimics of the organometallic active site cofactor of [FeFe]-hydrogenase, [Fe<small><sub>2</sub></small>(adt)(CO)<small><sub>6−<em>x</em></sub></small>(CN)<small><sub><em>x</em></sub></small>]<small><sup><em>x</em>−</sup></small> and [Fe<small><sub>2</sub></small>(pdt)(CO)<small><sub>6−<em>x</em></sub></small>(CN)<small><sub><em>x</em></sub></small>]<small><sup><em>x</em>−</sup></small> (<em>x</em> = 1, 2) as well as the corresponding cofactor variants of the enzyme by means of infrared, Mössbauer, and NMR spectroscopy. Additionally, we describe a straightforward synthetic recipe for the active site precursor complex Fe<small><sub>2</sub></small>(adt)(CO)<small><sub>6</sub></small>. Our data indicate that the aminodithiolate (adt) complex, which is the synthetic precursor of the natural active site cofactor, is most oxygen sensitive. This observation highlights the significance of proton transfer in aerobic deactivation, and supported by DFT calculations facilitates an identification of the responsible reactive oxygen species (ROS). Moreover, we show that the ligand environment of the iron ions critically influences the reactivity with O<small><sub>2</sub></small> and ROS like superoxide and H<small><sub>2</sub></small>O<small><sub>2</sub></small> as the oxygen sensitivity increases with the exchange of ligands from CO to CN<small><sup>−</sup></small>. The trends in aerobic deactivation observed for the model complexes are in line with the respective enzyme variants. Based on experimental and computational data, a model for the initial reaction of [FeFe]-hydrogenase with O<small><sub>2</sub></small> is developed. Our study underscores the relevance of model systems in understanding biocatalysis and validates their potential as important tools for elucidating the chemistry of oxygen-induced deactivation of [FeFe]-hydrogenase.</p>\",\"PeriodicalId\":99,\"journal\":{\"name\":\"Physical Chemistry Chemical Physics\",\"volume\":\" 28\",\"pages\":\" 19105-19116\"},\"PeriodicalIF\":2.9000,\"publicationDate\":\"2024-06-26\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://pubs.rsc.org/en/content/articlepdf/2024/cp/d3cp06048a?page=search\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Physical Chemistry Chemical Physics\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://pubs.rsc.org/en/content/articlelanding/2024/cp/d3cp06048a\",\"RegionNum\":3,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physical Chemistry Chemical Physics","FirstCategoryId":"92","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2024/cp/d3cp06048a","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
Oxygen sensitivity of [FeFe]-hydrogenase: a comparative study of active site mimics inside vs. outside the enzyme†
[FeFe]-hydrogenase is nature's most efficient proton reducing and H2-oxidizing enzyme. However, biotechnological applications are hampered by the O2 sensitivity of this metalloenzyme, and the mechanism of aerobic deactivation is not well understood. Here, we explore the oxygen sensitivity of four mimics of the organometallic active site cofactor of [FeFe]-hydrogenase, [Fe2(adt)(CO)6−x(CN)x]x− and [Fe2(pdt)(CO)6−x(CN)x]x− (x = 1, 2) as well as the corresponding cofactor variants of the enzyme by means of infrared, Mössbauer, and NMR spectroscopy. Additionally, we describe a straightforward synthetic recipe for the active site precursor complex Fe2(adt)(CO)6. Our data indicate that the aminodithiolate (adt) complex, which is the synthetic precursor of the natural active site cofactor, is most oxygen sensitive. This observation highlights the significance of proton transfer in aerobic deactivation, and supported by DFT calculations facilitates an identification of the responsible reactive oxygen species (ROS). Moreover, we show that the ligand environment of the iron ions critically influences the reactivity with O2 and ROS like superoxide and H2O2 as the oxygen sensitivity increases with the exchange of ligands from CO to CN−. The trends in aerobic deactivation observed for the model complexes are in line with the respective enzyme variants. Based on experimental and computational data, a model for the initial reaction of [FeFe]-hydrogenase with O2 is developed. Our study underscores the relevance of model systems in understanding biocatalysis and validates their potential as important tools for elucidating the chemistry of oxygen-induced deactivation of [FeFe]-hydrogenase.
期刊介绍:
Physical Chemistry Chemical Physics (PCCP) is an international journal co-owned by 19 physical chemistry and physics societies from around the world. This journal publishes original, cutting-edge research in physical chemistry, chemical physics and biophysical chemistry. To be suitable for publication in PCCP, articles must include significant innovation and/or insight into physical chemistry; this is the most important criterion that reviewers and Editors will judge against when evaluating submissions.
The journal has a broad scope and welcomes contributions spanning experiment, theory, computation and data science. Topical coverage includes spectroscopy, dynamics, kinetics, statistical mechanics, thermodynamics, electrochemistry, catalysis, surface science, quantum mechanics, quantum computing and machine learning. Interdisciplinary research areas such as polymers and soft matter, materials, nanoscience, energy, surfaces/interfaces, and biophysical chemistry are welcomed if they demonstrate significant innovation and/or insight into physical chemistry. Joined experimental/theoretical studies are particularly appreciated when complementary and based on up-to-date approaches.