Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2006-12-18
pubmed:abstractText
Sticholysin II (St II) is a cytolysin produced by the sea anemone Stichodactyla helianthus, characterized by forming oligomeric pores in natural and artificial membranes. In the present work the influence of the membrane lipidic components sphingomyelin (SM) and cholesterol (Cho) on binding and functional activity of St II, was evaluated using ELISA, lipid monolayers and liposomes. The aim of this work was to establish the promoting role of Cho and SM, both in St II binding and pore formation efficiency. In general the association (evaluated by ELISA and incorporation to phospholipid monolayers) of St II to lipids mixtures was better than to any one of the single components. Regarding the unique role of SM, it was found that, albeit inefficiently, St II binds to phosphatidylcholine (PC):Cho monolayers and liposomes, and is able to form active pores in these bilayers. The results in monolayers and liposomes show that the presence of SM and large amounts of Cho leads to the highest values of critical pressure and rate of association to monolayers, the most favorable interaction with liposomes, and the fastest rate of pore formation, in spite of the rigidity of the layers as suggested by the high generalized polarization (GP) of Laurdan incorporated to liposomes and FTIR data. Taken together, the present results show that the joint presence of SM and Cho, both in binary and ternary (PC containing) mixtures provide conditions particularly suitable for St II binding and function. We suggest that microdomains present in the bilayers could be important for toxin-membrane association.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0041-0101
pubmed:author
pubmed:issnType
Print
pubmed:volume
49
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
68-81
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Effect of sphingomyelin and cholesterol on the interaction of St II with lipidic interfaces.
pubmed:affiliation
Facultad de Biología, Universidad de la Habana, Centro de Estudio de Proteínas, Calle 25 no 455, CP 10400, Cuba. dmcb@fbio.uh.cu
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't