Modification of phospholipid composition in Pseudomonas strains induced by contact whit tetradecyltrimethylannomium

BOERIS, PS

Villa General Belgrano, Córdoba

Workshop; I Workshop on Current Topics in Pseudomonas y Burkholderia Research; 2007

P. putida tolerate and degrade high concentrations of cationic surfactant tetradecyltrimethyl ammonium (TDTMA). This adaptation to TDTMA might involve an initial mechanism producing changes at membrane levels involving the phospholipids (PL) composition. In this study, the relationship between the membrane PL composition and the resistance of P. putida A ATCC 12633 and P. putida KT2440 to the bactericidal activity of TDTMA was investigated. In cells exposed to TDTMA for 15 min the PL pattern was qualitatively the same as that observed in the absence of TDTMA but the amount of each individual PL, measured by Pi concentration or [32P]-Pi changed. With respect to control values in both strains phosphatidic acid (PA) and phosphatidylglycerol (PG) increased 140% and 120%, respectively; cardiolipin (CL) decreased about 60%. In TDTMA-adapted bacteria PA and PG increase 380% and 130%, respectively; CL decreased 70%. The changes in adapted cells were reverted after two subcultures without biocide. Respect to untreated bacteria, in cells exposed to TDTMA an increased activity phospholipase D hydrolyzing CL was detected. This activation suggests the participation of this enzyme in the formation of PA and PG necessary to maintain the integrity of the cell envelope and neutralize the high positive charge density given for TDTMA.