Fitness landscape of antibiotic tolerance in Pseudomonas aeruginosa biofilms.
Bacteria in biofilms have higher antibiotic tolerance than their planktonic counterparts. A major outstanding question is the degree to which the biofilm-specific cellular state and its constituent genetic determinants contribute to this hyper-tolerant phenotype. Here, we used genome-wide functional profiling of a complex, heterogeneous mutant population of Pseudomonas aeruginosa MPAO1 in biofilm and planktonic growth conditions with and without tobramycin to systematically quantify the contribution of each locus to antibiotic tolerance under these two states. We identified large sets of mutations that contribute to antibiotic tolerance predominantly in the biofilm or planktonic setting only, offering global insights into the differences and similarities between biofilm and planktonic antibiotic tolerance. Our mixed population-based experimental design recapitulated the complexity of natural biofilms and, unlike previous studies, revealed clinically observed behaviors including the emergence of quorum sensing-deficient mutants. Our study revealed a substantial contribution of the cellular state to the antibiotic tolerance of biofilms, providing a rational foundation for the development of novel therapeutics against P. aeruginosa biofilm-associated infections.
Department of Molecular Biology & Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America.
Sasan
S
Amini
Alison K
AK
Hottes
Lincoln E
LE
Smith
Saeed
S
Tavazoie
D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001483:Base Sequence; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D004361:Drug Tolerance / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial / Q000235:genetics; D056084:Genetic Fitness / Q000187:drug effects* / Q000235:genetics; D055106:Genome-Wide Association Study; D023281:Genomics; D015201:Meta-Analysis as Topic; D008969:Molecular Sequence Data; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D014031:Tobramycin / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D014031:Tobramycin