English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

Here we report on the purification, structural characterization, and biological activity of a glycolipid, 2- O -α-L-rhamnopyranosyl-α-L-rhamnopyranosyl-α( 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 α, 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.

biological chemistry

Endotoxin-like properties of a rhamnolipid exotoxin from  Burkholderia  ( Pseudomonas )  plantarii : immune cell stimulation and biophysical characterization