Linked Life Data

9765273

Source:http://linkedlifedata.com/resource/pubmed/id/9765273

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
42
pubmed:dateCreated
1998-11-6
pubmed:abstractText
A natural antibacterial peptide, cecropin B (CB), and designed analogs, CB-1 and CB-3, were synthesized. The three peptides have different structural characteristics, with CB having one hydrophobic and one amphipathic alpha-helix, CB-1 having two amphipathic alpha-helices, and CB-3 having two hydrophobic alpha-helices. These differences were used as the rationale for a study of their efficacy in breaking liposomes with different combinations of phosphatidic acid and phosphatidylcholine. Biosensor binding measurements and encapsulating dye leakage studies showed that the higher binding affinity of CB and CB-1 to the polar heads of lipids is not necessary for the peptides to be more effective at lysing lipid bilayers, especially when liposomes have a higher phosphatidic acid content. Kinetic studies, by intrinsic and extrinsic fluorescence stopped-flow measurements, revealed two transitional steps in liposome breakage by CB and CB-1, although only one kinetic step was found for CB-3. Circular dichroism stopped-flow measurements, monitoring the formation of secondary structure in the peptides, found one kinetic step for the interaction of all of the peptides with the liposomes. Also, the alpha-helical motif of the peptides was maintained after interacting with the liposomes. Based on these results, the mechanisms of liposome lysis by CB, CB-1, and CB-3 are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
16
pubmed:volume
273
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
27438-48
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
The dependence of membrane permeability by the antibacterial peptide cecropin B and its analogs, CB-1 and CB-3, on liposomes of different composition.
pubmed:affiliation
Department of Biochemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't