Linked Life Data

7492740

Source:http://linkedlifedata.com/resource/pubmed/id/7492740

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1996-1-11
pubmed:abstractText
CD and nmr spectroscopy were used to compare the conformational properties of two related peptides. One of the peptides, Model AB, was designed to adopt a helix-turn-extended strand (alpha beta) tertiary structure in water that might be stabilized by hydrophobic interactions between two leucine residues in the amino-terminal segment and two methionine residues in the carboxyl terminal segment. The other peptide, AB Helix, has the same amino acid sequence as Model AB except that it lacks the -Pro-Met-Thr-Met-Thr-Gly segment at the carboxyl-terminus. Although the carboxyl-terminal segment of Model AB was found to be unstructured, its presence increases the number of residues in a helical conformation, shifts the pKas of three ionizable side chains by 1 pH unit or more compared to an unstructured peptide, stabilizes the peptide as a monomer in high concentrations of ammonium sulfate, increases the conformational stability of residues at the terminal ends of the helix, and results in many slowly exchanging amide protons throughout the entire backbone of the peptide. These results suggest that interactions between adjacent segments in a small peptide can have significant structure organizing effects. Similar kinds of interactions may be important in determining the structure of early intermediates in protein folding and may be useful in the de novo design of independently folding peptides.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-3525
pubmed:author
pubmed:issnType
Print
pubmed:volume
36
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
109-20
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Design and characterization of a model alpha beta peptide.
pubmed:affiliation
Department of Chemistry and Biochemistry, University of Delaware, Newark 19716, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't