The stringent response modulates 4-hydroxy-2-alkylquinoline biosynthesis and quorum-sensing hierarchy in Pseudomonas aeruginosa.

Pseudomonas aeruginosa Density-Dependent Gene Expression in Sensing and Modulates Cell Stringent Response Activates Quorum

Burkholderia pseudomallei, B. thailandensis, and B. ambifaria produce 4-hydroxy-2-alkylquinoline analogues with a methyl group at the 3 position that is required for quorum-sensing regulation.

4-Hydroxy-2-alkylquinolines (HAQs), especially 3,4-dihydroxy-2-heptylquinoline (Pseudomonas quinolone signal) and its precursor, 4-hydroxy-2-heptylquinoline, are attracting much attention, mainly because of their role as signaling molecules in Pseudomonas aeruginosa. The pqsABCDE operon is centrally involved in their biosynthesis. The presence of a homologous operon in Burkholderia pseudomallei...

MexEF-OprN Efflux Pump Exports the Pseudomonas Quinolone Signal (PQS) Precursor HHQ (4-hydroxy-2-heptylquinoline)

Bacterial cells have evolved the capacity to communicate between each other via small diffusible chemical signals termed autoinducers. Pseudomonas aeruginosa is an opportunistic pathogen involved, among others, in cystic fibrosis complications. Virulence of P. aeruginosa relies on its ability to produce a number of autoinducers, including 4-hydroxy-2-alkylquinolines (HAQ). In a cell density-dep...

Interference with Pseudomonas quinolone signal synthesis inhibits virulence factor expression by Pseudomonas aeruginosa.

Pseudomonas aeruginosa is an opportunistic pathogen that controls numerous virulence factors through intercellular signals. This bacterium has two quorum-sensing systems (las and rhl), which act through the intercellular signals N-(3-oxododecanoyl)-l-homoserine lactone (3-oxo-C(12)-HSL) and N-butyryl-l-homoserine lactone (C(4)-HSL), respectively. P. aeruginosa also produces a third intercellula...

Low concentrations of local honey modulate ETA expression, and quorum sensing related virulence in drug-resistant Pseudomonas aeruginosa recovered from infected burn wounds

Objective(s): Honey’s ability to kill microorganisms and even eradication of chronic infections with drug-resistant pathogens has been documented by numerous studies. The present study is focused on the action of honey in its sub-inhibitory levels to impact on the pathogens coordinated behaviors rather than killing them. Materials and Methods:</strong...