Linked Life Data

1691014

Source:http://linkedlifedata.com/resource/pubmed/id/1691014

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1990-5-17
pubmed:abstractText
Model peptides with predetermined secondary, tertiary, and quaternary conformation have been successfully designed, synthesized, and characterized in an attempt to mimic the three-dimensional structure of an antigenic determinant. This work is a continuing effort to map the antigenic structure of the protein antigen lactate dehydrogenase C4 (LDH-C4) to develop a contraceptive vaccine. A putative topographic determinant with alpha alpha topology which associates into four-helix bundles was designed on the basis of the framework model of protein folding. An idealized amphiphilic 18-residue sequence (alpha 1) and a 40-residue alpha alpha fold (alpha 3) have been shown to form stable 4-helix structures in solution with a free energy of association on the order of -20.8 kcal/mol (tetramerization of alpha 1) and -7.8 kcal/mol (dimerization of alpha 3). Both alpha 1 and alpha 3 form stable monolayers at the air-water interface. The CD spectra of Langmuir-Blodgett monolayers are characteristically alpha-helical. Both CD and FTIR spectroscopic studies reval a high degree of secondary structure. The SAXS data strongly suggest that the helices are arranged in a four-helix bundle since the radius of gyration of 17.2 A and the vector distribution function are indicative of a prolate ellipsoid of axial dimensions and molecular weight appropriate for the four-helix bundle. The major contribution to the formation and stabilization of alpha 1 and alpha 3 is believed to be hydrophobic interaction between the amphiphilic alpha-helices. The displayed heptad repeat, helix dipole, ion pairs, and the loop sequence may have also contributed to the overall stability and antiparallel packing of the helices. A detailed structural analysis of a relevant topographic immunogenic determinant will elucidate the nature of antigen-antibody interactions as well as provide insight into protein folding intermediates.
pubmed:grant
pubmed:commentsCorrections
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
9
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
13-23
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Synthesis and biophysical characterization of engineered topographic immunogenic determinants with alpha alpha topology.
pubmed:affiliation
Department of Biochemistry and Molecular Biology and Cell Biology, Northwestern University, Evanston, Illinois 60208.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.