Fig. 6: Viability of pathogens isolated from sputum samples under different treatment conditions.

For each species and experimental group, viabilities of 7 strains of Staphylococcus aureus, 6 strains of Pseudomonas aeruginosa, and 5 strains of Achromobacter spp. obtained from sputum cultures assessed using colony-forming unit (CFU) tests. A pseudocount of 1 was added prior to log10 transformation due to the presence of zero counts. MolYsis had a strong negative effect on viability for Staphylococcus aureus (−4.3 log10 cells/mL, p-value < 0.001) thus was not further tested in gram-negative isolates. DNA/RNA shield, when added to unfrozen culture, universally rendered all isolates non-viable.