Linked Life Data

20187872

Source:http://linkedlifedata.com/resource/pubmed/id/20187872

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2010-4-14
pubmed:abstractText
Phosphatidylglycerol is a widely used mimetic to study the effects of AMPs (antimicrobial peptides) on the bacterial cytoplasmic membrane. However, the antibacterial activities of novel NK-2-derived AMPs could not be sufficiently explained by using this simple model system. Since the LPS (lipopolysaccharide)-containing outer membrane is the first barrier of Gram-negative bacteria, in the present study we investigated interactions of NK-2 and a shortened variant with viable Escherichia coli WBB01 and Proteus mirabilis R45, and with model membranes composed of LPS isolated from these two strains. Differences in net charge and charge distribution of the two LPS have been proposed to be responsible for the differential sensitivity of the respective bacteria to other AMPs. As imaged by TEM (transmission electron microscopy) and AFM (atomic force microscopy), NK-2-mediated killing of these bacteria was corroborated by structural alterations of the outer and inner membranes, the release of E. coli cytoplasma, and the formation of unique fibrous structures inside P. mirabilis, suggesting distinct and novel intracellular targets. NK-2 bound to and intercalated into LPS bilayers, and eventually induced the formation of transient heterogeneous lesions in planar lipid bilayers. However, the discriminative activity of NK-2 against the two bacterial strains was independent of membrane intercalation and lesion formation, which both were indistinguishable for the two LPS. Instead, differences in activity originated from the LPS-binding step, which could be demonstrated by NK-2 attachment to intact bacteria, and to solid-supported LPS bilayers on a surface acoustic wave biosensor.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1470-8728
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
427
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
477-88
pubmed:dateRevised
2010-6-29
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Lipopolysaccharide interaction is decisive for the activity of the antimicrobial peptide NK-2 against Escherichia coli and Proteus mirabilis.
pubmed:affiliation
Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't