title: A novel property of propolis (bee glue): anti-pathogenic activity by inhibition of N-acyl-homoserine lactone mediated signaling in bacteria.
abstract: BACKGROUND
  An alternative approach to antibiotics is the development of anti-pathogenic agents to control the bacterial virulome. Such anti-pathogenic agents could target a phenomena known as quorum sensing (QS).
  
  
  METHODS
  Six bacterial N-acyl-homoserine lactone (AHL)-dependent bioreporter strains were used to evaluate if bee hive glue also known as propolis contains constituents capable of inhibiting QS-controlled AHL signaling. In addition, the effect of propolis on the QS-dependent swarming motility was evaluated with the opportunisitic pathogen, Pseudomonas aeruginosa.
  
  
  RESULTS
  Differences in the propolis tincture samples were identified by physiochemical profiles and absorption spectra. Propolis tinctures at 0.0005% (v/v) that do not affect bacteria biosensor growth or the reporter system monitored were exposed to biosensors with and without the addition an AHL. No AHL signal mimics were found to be present in the propolis tinctures. However, when propolis and an inducer AHL signal were together exposed to five Escherichia coli and a Chromobacterium violaceum biosensor, propolis disrupted the QS bacterial signaling system in liquid- and agar-based bioassays and in C(18) reverse-phase thin-layer plate assays. Swarming motility in the opportunistic pathogen, Pseudomonas aeruginosa PAO1 and its AHL-dependent LasR- and RhlR-based QS behaviors were also inhibited by propolis.
  
  
  CONCLUSIONS
  Together, we present evidence that propolis contain compounds that suppress QS responses. In this regard, anti-pathogenic compounds from bee harvested propolis could be identified and isolated and thus will be valuable for the further development of therapeutics to disrupt QS signaling systems which regulate the virulome in many pathogenic bacteria.
authors: Molecular Bioscience and Biotechnology Program, School of Life Sciences, Rochester Institute of Technology, Rochester, NY 14623, USA.
authors: Zackery
authors: Z
authors: Bulman
authors: Phuong
authors: P
authors: Le
authors: André O
authors: AO
authors: Hudson
authors: Michael A
authors: MA
authors: Savka
mesh_terms: D054742:Acyl-Butyrolactones / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000378:metabolism; D015374:Biosensing Techniques; D002861:Chromobacterium / Q000187:drug effects / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects / Q000378:metabolism; D008156:Luciferases; D008163:Luminescent Measurements; D011429:Propolis / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000378:metabolism; D053038:Quorum Sensing / Q000187:drug effects*
chemical_list: D054742:Acyl-Butyrolactones; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D011429:Propolis; D008156:Luciferases