Quorum-sensing-deficient (lasR) mutants emerge at high frequency from a Pseudomonas aeruginosa mutS strain.

LUJAN A.M.; MOYANO A.J.; SEGURA I.; ARGARAÑA C.E; SMANIA A.M

SOC GENERAL MICROBIOLOGY

Año: 2007 vol. 153 p. 225 - 225

n Pseudomonas aeruginosa, quorum sensing constitutes a highly complex cell-to-cell communication system that, along with the cognate acylhomoserine lactone signals and regulators LasR and RhlR, modulates the production of virulence factors and a wide range of metabolic functions. In a previous paper, the authors reported that mismatch repair disruption in P. aeruginosa results in the spontaneous and reproducible emergence of defined morphological colony variantsafter a relatively short period of cultivation in an aerated rich medium, in contrast to the non-mutator parental strain, which does not display any kind of diversification under identical incubation conditions. One of the morphotypical variants, mS2, emerges at a high frequency and displays differences in virulence traits that could be regulated by major quorum-sensing regulators. The present study shows that mutS mS2 variants had defective LasR function due to simple but different point mutations along the lasR gene sequence,