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Pyocyanin degradation by a tautomerizing demethylase inhibits Pseudomonas aeruginosa biofilms.

ABSTRACT: The opportunistic pathogen Pseudomonas aeruginosa produces colorful redox-active metabolites called phenazines, which underpin biofilm development, virulence, and clinical outcomes. Although phenazines exist in many forms, the best studied is pyocyanin. Here, we describe pyocyanin demethylase (PodA), a hitherto uncharacterized protein that oxidizes the pyocyanin methyl group to formaldehyde and reduces the pyrazine ring via an unusual tautomerizing demethylation reaction. Treatment with PodA disrupts P. aeruginosa biofilm formation similarly to DNase, suggesting interference with the pyocyanin-dependent release of extracellular DNA into the matrix. PodA-dependent pyocyanin demethylation also restricts established biofilm aggregate populations experiencing anoxic conditions. Together, these results show that modulating extracellular redox-active metabolites can influence the fitness of a biofilm-forming microorganism.

SUBMITTER: Costa KC

PROVIDER: S-EPMC5303695 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Pyocyanin degradation by a tautomerizing demethylase inhibits Pseudomonas aeruginosa biofilms.

Costa Kyle C KC Glasser Nathaniel R NR Conway Stuart J SJ Newman Dianne K DK

Science (New York, N.Y.) 20161208 6321

The opportunistic pathogen Pseudomonas aeruginosa produces colorful redox-active metabolites called phenazines, which underpin biofilm development, virulence, and clinical outcomes. Although phenazines exist in many forms, the best studied is pyocyanin. Here, we describe pyocyanin demethylase (PodA), a hitherto uncharacterized protein that oxidizes the pyocyanin methyl group to formaldehyde and reduces the pyrazine ring via an unusual tautomerizing demethylation reaction. Treatment with PodA dis ...[more]

PMID: 27940577

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