Linked Life Data

19824734

Source:http://linkedlifedata.com/resource/pubmed/id/19824734

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
41
pubmed:dateCreated
2009-10-14
pubmed:abstractText
A major obstacle for future biohydrogen production is the oxygen sensitivity of [FeFe]-hydrogenases, the highly active catalysts produced by bacteria and green algae. The reactions of three representative [FeFe]-hydrogenases with O(2) have been studied by protein film electrochemistry under conditions of both H(2) oxidation and H(2) production, using CO as a complementary probe. The hydrogenases are DdHydAB and CaHydA from the bacteria Desulfovibrio desulfuricans and Clostridium acetobutylicum , and CrHydA1 from the green alga Chlamydomonas reinhardtii . Rates of inactivation depend on the redox state of the active site 'H-cluster' and on transport through the protein to reach the pocket in which the H-cluster is housed. In all cases CO reacts much faster than O(2). In the model proposed, CaHydA shows the most sluggish gas transport and hence little dependence of inactivation rate on H-cluster state, whereas DdHydAB shows a large dependence on H-cluster state and the least effective barrier to gas transport. All three enzymes show a similar rate of reactivation from CO inhibition, which increases upon illumination: the rate-determining step is thus assigned to cleavage of the labile Fe-CO bond, a reaction likely to be intrinsic to the atomic and electronic state of the H-cluster and less sensitive to the surrounding protein.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1520-5126
pubmed:author
pubmed:issnType
Electronic
pubmed:day
21
pubmed:volume
131
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
14979-89
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Electrochemical kinetic investigations of the reactions of [FeFe]-hydrogenases with carbon monoxide and oxygen: comparing the importance of gas tunnels and active-site electronic/redox effects.
pubmed:affiliation
Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't