Linked Life Data

7794895

Source:http://linkedlifedata.com/resource/pubmed/id/7794895

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
24
pubmed:dateCreated
1995-8-3
pubmed:abstractText
The radical chemistry of ferritin is incompletely understood. The present study was undertaken to investigate the production of radicals in H-chain recombinant human ferritin (HuHF) and mixed H/L-chain horse spleen ferritin (HoSF) and the potential role of radicals in the oxidative deposition of iron in these proteins. Radical production follows distinct pathways for the two proteins; an intact H-chain ferroxidase site is required for radical generation in both of them, however. With the H-chain HuHF, an EPR spectrum characteristic of a tyrosyl radical is seen following Fe2+ oxidation by O2 and, based on measurements with site-directed variants, is suggested to arise from residue Tyr-34 located in the vicinity of the ferroxidase site. The observation of this radical correlates with the observation of a 400-600 nm absorbance seen in stopped-flow kinetics studies which seems to require the presence of Tyr-34 (Bauminger et al. (1993) Biochem. J. 296, 709-714). The data are inconsistent, however, with the Tyr-34 radical being critically important in the protein-catalyzed mechanism of iron oxidation. Unlike HuHF, the radicals observed in L-chain-rich HoSF appear to arise from hydroxyl radical damage to the protein through Fenton chemistry. These latter radicals also appear to be centered on aromatic amino acids and may be derived from histidine.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
20
pubmed:volume
34
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7847-53
pubmed:dateRevised
2010-8-25
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Tyrosyl radical formation during the oxidative deposition of iron in human apoferritin.
pubmed:affiliation
Department of Chemistry, University of New Hampshire, Durham 03824, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't