Academic Editors: Massimo Conese and Lorenzo Guerra
Background: Cystic fibrosis (CF) is an autosomal recessive hereditary
disease that leads to the production of thickened mucus in the lungs, favouring
polymicrobial infections, such as chronic lung infections with the bacterial
opportunistic pathogen Pseudomonas aeruginosa. Method: A
biofilm model in combination with an adapted sampling and GC-MS analysis method
were applied to in vitro studies on different variables influencing the
composition of the extracellular volatile metabolome of P. aeruginosa.
Results: A significant influence on the metabolome could be demonstrated
for the culture medium as well as the atmosphere during cultivation (aerobic or
anaerobic). Furthermore, a significant influence of the mucoid
(alginate-overproducing) phenotype of the bacterium on quantity and composition
of volatile organic compounds could be observed. Based on the results a solid
culture medium was developed to simulate the nutrient conditions in the lungs of
a CF patient. The extracellular volatile metabolome of bacterial strains
P. aeruginosa ATCC 10145, PAO1 and FRD1 was characterized under CF-like
conditions. Conclusions: Bacterial strain-dependent metabolites were
identified. When P. aeruginosa PAO1 and FRD1 clinical isolates were
compared, 36 metabolites showed significant variations in intensities. When the
clinical isolates were compared with the reference strain (P. aeruginosa
ATCC 10145), 28 metabolites (P. aeruginosa PAO1) and 70 metabolites
(P. aeruginosa FRD1) were determined whose peaks showed significant
deviation (p
