Analysis of the Phospholipid Profile of the Collection Strain PAO1 and Clinical Isolates of Pseudomonas aeruginosa in Relation to Their Attachment Capacity

Abstract

Bacteria form multicellular and resistant structures named biofilms. Biofilm formation starts with the attachment phase, and the molecular actors involved in this phase, except adhesins, are poorly characterized. There is growing evidence that phospholipids are more than simple structural bricks. They are involved in bacterial adaptive physiology, but little is known about their role in biofilm formation. Here, we report a mass spectrometry analysis of the phospholipid (PL) profile of several strains of Pseudomonas aeruginosa isolated from cystic fibrosis patients. The aim of our study was to evaluate a possible link between the PL profile of a strain and its attachment phenotype. Our results showed that PL profile is strongly strain-dependent. The PL profile of P. aeruginosa PAO1, a collection strain, was different from those of 10 clinical isolates characterized either by a very low or a very high attachment capacity. We observed also that the clinical strain’s PL profiles varied even more importantly between isolates. By comparing groups of strains having similar attachment capacities, we identified one PL, PE 18:1-18:1, as a potential molecular actor involved in attachment, the first step in biofilm formation. This PL represents a possible target in the fight against biofilms.

Comparison of Small Biomolecule Ionization and Fragmentation in Pseudomonas aeruginosa Using Common MALDI Matrices

“…Quinolones, phospholipids, and rhamnolipids were identified across all six matrices. These surface associated molecules are known to play roles in signaling and structural composition of P. aeruginosa . , Some amino acids, lactones, and other small biomolecules were also identified, but due to low ionization in the lower m / z range, these were not commonly observed across all matrices. The identified ions (Figure a) and molecules (Figure b) revealed the selectivity of each matrix.…”