Linked Life Data

3542363

Source:http://linkedlifedata.com/resource/pubmed/id/3542363

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1987-3-10
pubmed:abstractText
The molecular architecture of anaphylatoxins has been explored on several levels. Primary, secondary and tertiary structural parameters that dictate function of the C3a, C4a and C5a molecules are being elucidated with the aid of comparative sequence analyses, physical measurements and organic syntheses. Although C3a, C4a and C5a are biologically distinct mediators, as defined by their unique receptor systems, a common genetic origin is apparent from conserved features in their primary structures. Evidence is now available which suggests that similarities in the folding pattern of the anaphylatoxins may dictate a concensus conformation for each factor. We have learned from synthetic peptide studies that the binding (e.g. effector) site in anaphylatoxin molecules exists as a linear sequence contained in the C-terminal portion of the polypeptide. What is also evident is that a preferred conformation is defined for the binding site requiring a proper side chain orientation for optimal bioactivity. It is proposed that folding of the native structure stabilizes this conformation at the binding site. The binding site in C3a contains the essential residues LGLAR folded in an irregular or pseudo-beta-turn and stabilized by an adjacent alpha-helical segment. It is proposed that the alpha-helical segment influences orientation of the side chain residues in the 'binding site'. A similar model is evolving for C5a based on synthetic C5a peptides that express both spasmogenic and chemotactic activities. This helix turn model promises to be representative of an essential structural feature that determines anaphylatoxin activity. We believe that these models contribute significantly to our understanding of the molecular relationships between structure and function for these humoral mediators of inflammation.
pubmed:grant
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0253-5076
pubmed:author
pubmed:issnType
Print
pubmed:volume
3
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
111-27
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Biochemistry and biology of anaphylatoxins.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Review