Determining Multiple Responses of Pseudomonas aeruginosa PAO1 to an Antimicrobial Agent, Free Nitrous Acid.
Free nitrous acid (FNA) has recently been demonstrated as an antimicrobial agent on a range of micro-organisms, especially in wastewater-treatment systems. However, the antimicrobial mechanism of FNA is largely unknown. Here, we report that the antimicrobial effects of FNA are multitargeted. The response of a model denitrifier, Pseudomnas aeruginosa PAO1 (PAO1), common in wastewater treatment, was investigated in the absence and presence of inhibitory level of FNA (0.1 mg N/L) under anaerobic denitrifying conditions. This was achieved through coupling gene expression analysis, by RNA sequencing, and with a suite of physiological analyses. Various transcripts exhibited significant changes in abundance in the presence of FNA. Respiration was likely inhibited because denitrification activity was severely depleted, and decreased transcript levels of most denitrification genes occurred. As a consequence, the tricarboxylic acid (TCA) cycle was inhibited due to the lowered cellular redox state in the FNA-exposed cultures. Meanwhile, during FNA exposure, PAO1 rerouted its carbon metabolic pathway from the TCA cycle to pyruvate fermentation with acetate as the end product as a possible survival mechanism. Additionally, protein synthesis was significantly decreased, and ribosome preservation was evident. These findings improve our understanding of PAO1 in response to FNA and contribute toward the potential application for use of FNA as an antimicrobial agent.
Advanced Water Management Centre, The University of Queensland , St. Lucia, Brisbane QLD 4072, Australia.
Shu-Hong
SH
Gao
Advanced Water Management Centre, The University of Queensland , St. Lucia, Brisbane QLD 4072, Australia.|iCarbonX , Shenzhen 518053, China.
Lu
L
Fan
Advanced Water Management Centre, The University of Queensland , St. Lucia, Brisbane QLD 4072, Australia.|Laboratory of Microbial Ecology and Technology (LabMET), Ghent University , Coupure Links 653, Ghent 9000, Belgium.
Lai
L
Peng
Advanced Water Management Centre, The University of Queensland , St. Lucia, Brisbane QLD 4072, Australia.
Jianhua
J
Guo
Advanced Water Management Centre, The University of Queensland , St. Lucia, Brisbane QLD 4072, Australia.
Míriam
M
Agulló-Barceló
Advanced Water Management Centre, The University of Queensland , St. Lucia, Brisbane QLD 4072, Australia.
Zhiguo
Z
Yuan
Advanced Water Management Centre, The University of Queensland , St. Lucia, Brisbane QLD 4072, Australia.
Philip L
PL
Bond
D000890:Anti-Infective Agents; D058440:Denitrification / Q000187:drug effects; D009608:Nitrous Acid; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D062065:Wastewater
D000890:Anti-Infective Agents; D009608:Nitrous Acid; D062065:Wastewater