Linked Life Data

7037052

Source:http://linkedlifedata.com/resource/pubmed/id/7037052

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1982-5-27
pubmed:abstractText
The Raman spectrum of the B2 subunit of Escherichia coli ribonucleotide reductase shows a peak at 496 cm-1 that appears to be in resonance with the 370-nm electronic transition of the binuclear iron center in both the native and radical-free forms of the protein. Exposure of the protein to H218O causes the peak to shift to 481 cm-1, indicating that the vibrational mode is due to an Fe-O moiety in which the oxygen can exchange with solvent. The rate of oxygen exchange (kobsd = 8.3 x 10-4 s-1) is consistent with a mu-oxo-bridged structure. Protonation of the oxygen is unlikely since the Fe-O vibration fails to shift to lower frequency in D2O. Instead, there is a gradual increase in the vibrational frequency with time to a maximum value of 502 cm-1 after 3 h in 70% with time to a maximum value of 602 cm-1 after 3 h in 70% D2O. Apparently, the deuteration of successive protein functional groups causes a slight alteration in the structure of the binuclear iron center. The resonance Raman characteristics of the Fe-O-Fe group in protein B2 are similar to those previously reported for the mu-oxo-bridged binuclear iron center in hemerythrin. A further similarity between the two proteins is the high degree of alpha-helical content. Circular dichroism measurements place this value at approximately 60% for the B2 subunit of ribonucleotide reductase.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
96-102
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1982
pubmed:articleTitle
Raman spectral evidence for a mu-oxo bridge in the binuclear iron center of ribonucleotide reductase.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't