Linked Life Data

21236241

Source:http://linkedlifedata.com/resource/pubmed/id/21236241

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2011-3-11
pubmed:abstractText
Previous studies with Geobacter sulfurreducens have demonstrated that OmcS, an abundant c-type cytochrome that is only loosely bound to the outer surface, plays an important role in electron transfer to Fe(III) oxides as well as other extracellular electron acceptors. In order to further investigate the function of OmcS, it was purified from a strain that overproduces the protein. Purified OmcS had a molecular mass of 47015 Da, and six low-spin bis-histidinyl hexacoordinated heme groups. Its midpoint redox potential was -212 mV. A thermal stability analysis showed that the cooperative melting of purified OmcS occurs in the range of 65-82 °C. Far UV circular dichroism spectroscopy indicated that the secondary structure of purified OmcS consists of about 10% ?-helix and abundant disordered structures. Dithionite-reduced OmcS was able to transfer electrons to a variety of substrates of environmental importance including insoluble Fe(III) oxide, Mn(IV) oxide and humic substances. Stopped flow analysis revealed that the reaction rate of OmcS oxidation has a hyperbolic dependence on the concentration of the studied substrates. A ten-fold faster reaction rate with anthraquinone-2,6-disulfonate (AQDS) (25.2 s?¹) was observed as compared to that with Fe(III) citrate (2.9 s?¹). The results, coupled with previous localization and gene deletion studies, suggest that OmcS is well-suited to play an important role in extracellular electron transfer.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0006-3002
pubmed:author
pubmed:copyrightInfo
Copyright © 2011 Elsevier B.V. All rights reserved.
pubmed:issnType
Print
pubmed:volume
1807
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
404-12
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Biochemical characterization of purified OmcS, a c-type cytochrome required for insoluble Fe(III) reduction in Geobacter sulfurreducens.
pubmed:affiliation
Department of Microbiology, University of Massachusetts, Amherst, MA, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't