Novel persistence genes in Pseudomonas aeruginosa identified by high-throughput screening

Persister cells are phenotypic variants that are extremely tolerant to high concentrations
of antibiotics. They constitute a fraction of stationary phase cultures and
biofilm populations of numerous bacterial species, such as the opportunistic
pathogen Pseudomonas aeruginosa. Even though persisters are believed to be an
important cause of incomplete elimination of infectious populations by antibiotics,
their nature remains obscure. Most studies on persistence have focused on the model
organism Escherichia coli and only a limited number of persistence genes have been
identified to date.We performed the first large-scale screening of a P. aeruginosa PA14
mutant library to identify novel genes involved in persistence. A total of 5000 mutants
were screened in a high-throughput manner and nine new persistence mutants were
identified. Four mutants (with insertions in dinG, spuC, PA14_17880 and
PA14_66140) exhibited a low persister phenotype and five mutants (in algR, pilH,
ycgM, pheA and PA14_13680) displayed high persistence. These genes may serve as
new candidate drug targets in the combat against P. aeruginosa infections.

Publication year:2009

Keywords:Pseudomonas, Persisters, Antibiotics