Pseudomonadaceae was found to contribute to the community composition, although not detectable by culture, however, in exacerbating samples it contributed, on average 0.2%

whereas, in stable samples it contributed 13% to the total community composition. The role of environmental variables in driving bacterial community structure In order to investigate impact of patient specific and clinical variable on the bacterial community structures the bacterial profiles from the patient cohort were subjected to ordination analysis (CCA) phosphatase inhibitor library and permutation testing. Analyses were performed on the bacterial community resolved to family level then repeated with putative species level resolution. These analyses constrained the community profile variance with 13 measured variables (Culture positive sputum; H. SN-38 clinical trial influenzae detected by culture; P. aeruginosa detected by culture; the presence of an exacerbation at time of sampling; 12 month history of persistent;

intermittent or absence Lazertinib of culturable P. aeruginosa, antibiotic treatment in previous month; current azithromycin treatment; current nebulised colistin treatment; gender, FEV1% predicted and age) derived from patient records. For the family level analyses, these variables explained 64.4% of the total variance in the data but only three were significantly associated with the variance in bacterial community structure. These were culture positive sputum (P = 0.016); the

presence of culturable H. influenzae (P = 0.002); and culturable P. aeruginosa (P = 0.002) (Figure 1A). Figure 1 Canonical correspondence analysis of (A) total cohort showing that sputum samples that were culture positive ( P =  0.016); had culturable P. aeruginosa ( P =  0.002) and culturable H. influenzae ( P =  0.002) were associated with distinct bacterial community assemblies, (B) Frequent exacerbators also showing that samples that were culture Amine dehydrogenase positive ( P =  0.05); had culturable P. aeruginosa ( P =  0.002) and culturable H. influenzae ( P =  0.002) were associated with distinct bacterial community assemblies. Discrete variables, indicated by ▲, are; Culture positive sputum; H.i, H. influenzae detected by culture and P.a, P. aeruginosa detected by culture. Other variables analysed; the presence of an exacerbation at time of sampling; 12 month history of persistent; intermittent or absence of culturable P. aeruginosa, current azithromycin treatment; current nebulised colistin treatment; gender, FEV1% predicted; frequent exacerbation and age. None were found to significantly affect the community structure and for clarity are not shown. Percentage values show variance within data explained by that axis.