Please wait, while we are loading the content...
Please wait, while we are loading the content...
| Content Provider | Springer Nature Link |
|---|---|
| Author | Roseboom, Winfried Lacey, Antonio L. Fernandez, Victor M. Hatchikian, E. Claude Albracht, Simon P. J. |
| Copyright Year | 2005 |
| Abstract | In [FeFe]-hydrogenases, the H cluster (hydrogen-activating cluster) contains a di-iron centre ([2Fe]H subcluster, a (L)(CO)(CN)Fe(μ-RS2)(μ-CO)Fe(CysS)(CO)(CN) group) covalently attached to a cubane iron-sulphur cluster ([4Fe-4S]H subcluster). The Cys-thiol functions as the link between one iron (called Fe1) of the [2Fe]H subcluster and one iron of the cubane subcluster. The other iron in the [2Fe]H subcluster is called Fe2. The light sensitivity of the Desulfovibrio desulfuricans enzyme in a variety of states has been studied with infrared (IR) spectroscopy. The aerobic inactive enzyme (Hinact state) and the CO-inhibited active form (Hox–CO state) were stable in light. Illumination of the Hox state led to a kind of cannibalization; in some enzyme molecules the H cluster was destroyed and the released CO was captured by the H clusters in other molecules to form the light-stable Hox–CO state. Illumination of active enzyme under 13CO resulted in the complete exchange of the two intrinsic COs bound to Fe2. At cryogenic temperatures, light induced the photodissociation of the extrinsic CO and the bridging CO of the enzyme in the Hox–CO state. Electrochemical redox titrations showed that the enzyme in the Hinact state converts to the transition state (Htrans) in a reversible one-electron redox step (E m, pH 7=–75 mV). IR spectra demonstrate that the added redox equivalent not only affects the [4Fe-4S]H subcluster, but also the di-iron centre. Enzyme in the Htrans state reacts with extrinsic CO, which binds to Fe2. The Htrans state converts irreversibly into the Hox state in a redox-dependent reaction most likely involving two electrons (E m, pH 7=–261 mV). These electrons do not end up on any of the six Fe atoms of the H cluster; the possible destiny of the two redox equivalents is discussed. An additional reversible one-electron redox reaction leads to the Hred state (E m, pH 7=–354 mV), where both Fe atoms of the [2Fe]H subcluster have the same formal oxidation state. The possible oxidation states of Fe1 and Fe2 in the various enzyme states are discussed. Low redox potentials (below –500 mV) lead to destruction of the [2Fe]H subcluster. |
| Starting Page | 102 |
| Ending Page | 118 |
| Page Count | 17 |
| File Format | |
| ISSN | 09498257 |
| Journal | JBIC Journal of Biological Inorganic Chemistry |
| Volume Number | 11 |
| Issue Number | 1 |
| e-ISSN | 14321327 |
| Language | English |
| Publisher | Springer-Verlag |
| Publisher Date | 2005-12-02 |
| Publisher Place | Berlin, Heidelberg |
| Access Restriction | One Nation One Subscription (ONOS) |
| Subject Keyword | [FeFe]-hydrogenase Redox titration Light sensitivity Infrared Carbon monoxide Exchange Microbiology Biochemistry |
| Content Type | Text |
| Resource Type | Article |
| Subject | Biochemistry Inorganic Chemistry |
National Digital Library of India (NDLI) is a virtual repository of learning resources which is not just a repository with search/browse facilities but provides a host of services for the learner community. It is sponsored and mentored by Ministry of Education, Government of India, through its National Mission on Education through Information and Communication Technology (NMEICT). Filtered and federated searching is employed to facilitate focused searching so that learners can find the right resource with least effort and in minimum time. NDLI provides user group-specific services such as Examination Preparatory for School and College students and job aspirants. Services for Researchers and general learners are also provided. NDLI is designed to hold content of any language and provides interface support for 10 most widely used Indian languages. It is built to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is designed to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is developed, operated and maintained from Indian Institute of Technology Kharagpur.
Learn more about this project from here.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Education, through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
| Sl. | Authority | Responsibilities | Communication Details |
|---|---|---|---|
| 1 | Ministry of Education (GoI), Department of Higher Education |
Sanctioning Authority | https://www.education.gov.in/ict-initiatives |
| 2 | Indian Institute of Technology Kharagpur | Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project | https://www.iitkgp.ac.in |
| 3 | National Digital Library of India Office, Indian Institute of Technology Kharagpur | The administrative and infrastructural headquarters of the project | Dr. B. Sutradhar bsutra@ndl.gov.in |
| 4 | Project PI / Joint PI | Principal Investigator and Joint Principal Investigators of the project |
Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon |
| 5 | Website/Portal (Helpdesk) | Queries regarding NDLI and its services | support@ndl.gov.in |
| 6 | Contents and Copyright Issues | Queries related to content curation and copyright issues | content@ndl.gov.in |
| 7 | National Digital Library of India Club (NDLI Club) | Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach | clubsupport@ndl.gov.in |
| 8 | Digital Preservation Centre (DPC) | Assistance with digitizing and archiving copyright-free printed books | dpc@ndl.gov.in |
| 9 | IDR Setup or Support | Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops | idr@ndl.gov.in |
|
Loading...
|