TY - JOUR
T1 - Adaptation of Pseudomonas aeruginosa to the chronic phenotype by mutations in the algTmucABD operon in isolates from Brazilian cystic fibrosis patients
AU - Caçador, Natália Candido
AU - Paulino da Costa Capizzani, Carolina
AU - Monteiro Marin Torres, Lídia Alice Gomes
AU - Galetti, Renata
AU - Ciofu, Oana
AU - Lúcia da Costa Darini, Ana
AU - Høiby, Niels
PY - 2018
Y1 - 2018
N2 - Chronic lung infection by Pseudomonas aeruginosa is the leading cause of morbidity and mortality in cystic fibrosis (CF) patients. This is associated with the conversion of the non-mucoid to the mucoid phenotype. However, there is little information about the occurrence of alginate-producing P. aeruginosa in CF patients outside Europe and North America. The aim of the present study was to investigate mutations in the algTmucABD operon in mucoid and non-mucoid isolates from Brazilian CF patients. Twenty-seven mucoid and 37 non-mucoid isolates from 40 CF patients chronically infected by P. aeruginosa attending a CF reference center in Brazil were evaluated by sequence analysis. Mutations in mucA were observed in 93% of the mucoid isolates and 54% of the non-mucoid isolates. Among these non-mucoid isolates, 55% were considered revertants, since they also had mutations in algT (algU). Most isolates associated with moderate alginate production presented point mutations in mucB and/or mucD. We identified 30 mutations not previously described in the operon. In conclusion, mutations in mucA were the main mechanism of conversion to mucoidy, and most of the non-mucoid isolates were revertants, but the mechanism of revertance is not fully explained by changes in algT.
AB - Chronic lung infection by Pseudomonas aeruginosa is the leading cause of morbidity and mortality in cystic fibrosis (CF) patients. This is associated with the conversion of the non-mucoid to the mucoid phenotype. However, there is little information about the occurrence of alginate-producing P. aeruginosa in CF patients outside Europe and North America. The aim of the present study was to investigate mutations in the algTmucABD operon in mucoid and non-mucoid isolates from Brazilian CF patients. Twenty-seven mucoid and 37 non-mucoid isolates from 40 CF patients chronically infected by P. aeruginosa attending a CF reference center in Brazil were evaluated by sequence analysis. Mutations in mucA were observed in 93% of the mucoid isolates and 54% of the non-mucoid isolates. Among these non-mucoid isolates, 55% were considered revertants, since they also had mutations in algT (algU). Most isolates associated with moderate alginate production presented point mutations in mucB and/or mucD. We identified 30 mutations not previously described in the operon. In conclusion, mutations in mucA were the main mechanism of conversion to mucoidy, and most of the non-mucoid isolates were revertants, but the mechanism of revertance is not fully explained by changes in algT.
U2 - 10.1371/journal.pone.0208013
DO - 10.1371/journal.pone.0208013
M3 - Journal article
C2 - 30496246
AN - SCOPUS:85057558546
SN - 1932-6203
VL - 13
JO - PLoS Computational Biology
JF - PLoS Computational Biology
IS - 11
M1 - e0208013
ER -