Metabolic Phenotyping and Strain Characterisation of Pseudomonas aeruginosa Isolates from Cystic Fibrosis Patients Using Rapid Evaporative Ionisation Mass Spectrometry

Sci Rep. 2018 Jul 19;8(1):10952. doi: 10.1038/s41598-018-28665-7.

Abstract

Rapid evaporative ionisation mass spectrometry (REIMS) is a novel technique for the real-time analysis of biological material. It works by conducting an electrical current through a sample, causing it to rapidly heat and evaporate, with the analyte containing vapour channelled to a mass spectrometer. It was used to characterise the metabolome of 45 Pseudomonas aeruginosa (P. aeruginosa) isolates from cystic fibrosis (CF) patients and compared to 80 non-CF P. aeruginosa. Phospholipids gave the highest signal intensity; 17 rhamnolipids and 18 quorum sensing molecules were detected, demonstrating that REIMS has potential for the study of virulence-related metabolites. P. aeruginosa isolates obtained from respiratory samples showed a higher diversity, which was attributed to the chronic nature of most respiratory infections. The analytical sensitivity of REIMS allowed the detection of a metabolome that could be used to classify individual P. aeruginosa isolates after repeated culturing with 81% accuracy, and an average 83% concordance with multilocus sequence typing. This study underpins the capacities of REIMS as a tool with clinical applications, such as metabolic phenotyping of the important CF pathogen P. aeruginosa, and highlights the potential of metabolic fingerprinting for fine scale characterisation at a sub-species level.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Typing Techniques
  • Cystic Fibrosis / microbiology*
  • Humans
  • Metabolomics / methods*
  • Multilocus Sequence Typing
  • Phenotype
  • Pseudomonas Infections / microbiology*
  • Pseudomonas aeruginosa / classification*
  • Pseudomonas aeruginosa / isolation & purification
  • Pseudomonas aeruginosa / metabolism
  • Pseudomonas aeruginosa / pathogenicity
  • Quorum Sensing
  • Sensitivity and Specificity
  • Spectrometry, Mass, Electrospray Ionization
  • Virulence