Linked Life Data

21241054

Source:http://linkedlifedata.com/resource/pubmed/id/21241054

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2011-3-1
pubmed:abstractText
To gain insight into the effects of amidation on the mechanism of membrane interaction, we studied two peptides modelin-5-COOH and modelin-5-CONH(2) and found they exhibit high surface activities (23.2 and 27.1 mN/m, respectively). When they were tested against Escherichia coli, amidation was seen to increase efficacy approximately 10-fold. Our results demonstrated that both peptides adopted low levels of ?-helix in solution (<20%); however, in the presence of E. coli lipid extract, modelin-5-CONH(2) had a greater propensity (69%) than modelin-5-COOH (32%) to generate ?-helical structure. The binding coefficient for both peptides was ?10 ?M, and the Hill coefficient approximated 1, suggesting that for both peptides the interactions with E. coli membranes were monomeric and comparable in strength. The peptides showed a clear preference for anionic lipid, with monolayer data showing that enhanced levels of helicity were associated with a greater pressure change (?6 mN/m). Use of fluorescein-phosphatidylethanolamine showed the amidated version was able to generate greater levels of membrane disruption, which was confirmed by thermodynamic analysis. The data would imply that both peptides are able to initially bind to bilayer structures, but upon binding, the amidation stabilizes helix formation. This would be expected to help overcome a key rate-limiting step and generate higher local concentrations of peptide at the bilayer interface, which in turn would be predicted to increase efficacy.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1520-4995
pubmed:author
pubmed:issnType
Electronic
pubmed:day
8
pubmed:volume
50
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1514-23
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Influence of C-terminal amidation on the efficacy of modelin-5.
pubmed:affiliation
School of Pharmacy and Biomedical Sciences, University of Central Lancashire, Preston PR1 2HE, U.K.
pubmed:publicationType
Journal Article