Linked Life Data

228705

Source:http://linkedlifedata.com/resource/pubmed/id/228705

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
22
pubmed:dateCreated
1980-2-26
pubmed:abstractText
Of the 82 three dimensionally characterized residues of cytochrome c551, 49 are found to be structurally and topologically equivalent to the globin fold and 41 are equivalent to the cytochrome b5 fold, with a respective root mean square separation of 3.5 and 4.9 A between equivalenced Calpha atoms. The common fold represents a central heme binding core, corresponding to the middle exon of certain globin genes. After superposition of the protein folds, the heme irons are found to be separated by 5.4 and 1.6 A, while their heme normals are inclined by 6 degrees and 32 degrees, respectively. Furthermore, the heme "face", determined by the asymmetric attachment of the vinyl and propionyl side chains, is directed similarly in all three heme proteins. The heme itself is rotated by 72 degrees and 116 degrees about its normal, respectively. The minimum base change per codon for the three pairwise comparisons corresponds to the expected value of random sequence comparisons. While all three heme proteins may have diverged from a common ancestor, their similarity may have arisen from the requirements of heme binding or the utilization of a particularly stable fold. Known structures within commonly accepted divergent families were superimposed in order to discriminate better between convergence and divergence. Minimum base changes per codon, number of deletions and insertions, percentage of equivalenced residues, precision of heme superposition, and root mean square separation of equivalenced Calpha atoms were tested as measures of evolutionary relationships.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
30
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4951-60
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1979
pubmed:articleTitle
Structural comparisons of heme binding proteins.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.