Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2006-3-17
pubmed:abstractText
Here we report on the purification, structural characterization, and biological activity of a glycolipid, 2-O-alpha-L-rhamnopyranosyl-alpha-L-rhamnopyranosyl-alpha(R)-3-hydroxytetradecanoyl-(R)-3-hydroxytetradecanoate (RL-2,2(14)) produced by Burkholderia (Pseudomonas) plantarii. RL-2,2(14) is structurally very similar to a rhamnolipid exotoxin from Pseudomonas aeruginosa and identical to the rhamnolipid of Burkholderia pseudomallei, the causative agent of melioidosis. Interestingly, RL-2,2(14) exhibits strong stimulatory activity on human mononuclear cells to produce tumor necrosis factor alpha, the overproduction of which is known to cause sepsis and the septic shock syndrome. Such a property has not been noted so far for rhamnolipid exotoxins, only for bacterial endotoxins (lipopolysaccharide, LPS). Consequently, we analyzed RL-2,2(14) with respect to its pathophysiological activities as a heat-stable extracellular toxin. Like LPS, the cell-stimulating activity of the rhamnolipid could be inhibited by incubation with polymyxin B. However, immune cell activation by RL-2,2(14) does nor occur via receptors that are involved in LPS (TLR4) or lipopeptide signaling (TLR2). Despite its completely different chemical structure, RL-2,2(14) exhibits a variety of endotoxin-related physicochemical characteristics, such as a cubic-inverted supramolecular structure. These data are in good agreement with our conformational concept of endotoxicity: intercalation of naturally originating virulence factors into the immune cell membrane leads to strong mechanical stress on integral proteins, eventually causing cell activation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1431-6730
pubmed:author
pubmed:issnType
Print
pubmed:volume
387
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
301-10
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Endotoxin-like properties of a rhamnolipid exotoxin from Burkholderia (Pseudomonas) plantarii: immune cell stimulation and biophysical characterization.
pubmed:affiliation
Forschungszentrum Borstel, Leibniz-Zentrum for Medizin und Biowissenschaften, Parkallee 10, D-23845 Borstel, Germany. jandrae@fz-borstel.de
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't