Linked Life Data

2071033

Source:http://linkedlifedata.com/resource/pubmed/id/2071033

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1991-8-22
pubmed:abstractText
Using the complete sequences for MnSOD from Thermus thermophilus and for FeSOD from E. coli, structural models for both oxidized enzymes have been refined, the Mn protein to an R of 0.186 for all data between 10.0 and 1.8 A, and the Fe protein to an R of 0.22 for data between 10.0 and 2.5 A. The results of the refinements support the presence of a solvent as a fifth ligand to Mn(III) and Fe(III) and a coordination geometry that is close to trigonal bipyramidal. The putative substrate-entry channel is comprised of residues from both subunits of the dimer; several basic residues that are conserved may facilitate approach of O2-, while other conserved residues maintain interchain packing interactions. Analysis of the azide complex of Fe(III) dismutase suggests that during turnover O2- binds to the metal at a sixth coordination site without displacing the solvent ligand. Because crystals reduced with dithionite show no evidence for displacement of the protein ligands, the redox-linked proton acceptor (C. Bull and J.A. Fee (1985), Journal of the American Chemistry Society 107, 3295-3304) is unlikely to be one of the histidines which bind the metal ion. Structural, kinetic, titration, and spectroscopic data can be accommodated in a mechanistic scheme which accounts for the differential titration behaviour of the Fe(III) and Fe(II) enzymes at neutral and high pH.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
8755-0199
pubmed:author
pubmed:issnType
Print
pubmed:volume
12-13 Pt 1
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
259-68
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Structure-function relationships in iron and manganese superoxide dismutases.
pubmed:affiliation
Biophysics Research Division, University of Michigan.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.