Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

The effect of IAN on P. aeruginosa virulence

ABSTRACT: Intercellular signal indole and its derivative hydroxyindoles inhibit Escherichia coli biofilm and diminish Pseudomonas aeruginosa virulence. However, indole and bacterial indole derivatives were unstable in microbial community due to the widespread of diverse oxygenases that could quickly degrade them. Hence, we sought to identify novel non-toxic, stable, and potent indole derivatives from plant sources for inhibiting biofilm formation of E. coli O157:H7 and P. aeruginosa PAO1. Here, plant auxin 3-indolylacetonitrile (IAN) was found to inhibit biofilm formation of both E. coli O157:H7 and P. aeruginosa without affecting its growth. IAN inhibited biofilms more effectively than indole for both E. coli and P. aeruginosa. Additionally, IAN decreased the production of virulence factor pyocyanin in P. aeruginosa. DNA microarray analysis indicated that IAN repressed genes involved in curli formation and glycerol metabolism, while IAN induced indole-related genes and prophage genes in E. coli. It appears that IAN inhibits biofilm formation of E. coli by reducing curli formation and inducing indole production. Furthermore, unlike bacterial indole derivatives, plant-originated IAN was stable in the presence of either E. coli or P. aeruginosa. For the microarray experiments, P. aeruginosa were inoculated in 25 ml of LB medium in 250 ml shake flasks with overnight cultures that were diluted 1:100. IAN (100 μg/ml) dissolved in 25 μl DMSO or 25 μl DMSO alone as a control was added. Cells were cultured in LB at 37C with 250 rpm shakingfor 5 hrs. Cells were immediately chilled with dry ice and 95% ethanol (to prevent RNA degradation) for 30 sec before centrifugation in 50 ml centrifuge tubes at 13,000 g for 2 min; cell pellets were frozen immediately with dry ice and stored -80°C. RNA was isolated using Qiagen RNeasy mini Kit (Valencia, CA, USA). RNA quality was assessed by Agilent 2100 bioanalyser using the RNA 6000 Nano Chip (Agilent Technologies, Amstelveen, The Netherlands), and quantity was determined by ND-1000 Spectrophotometer (NanoDrop Technologies, Inc., DE, USA).

ORGANISM(S): Pseudomonas aeruginosa

SUBMITTER: Jintae Lee

PROVIDER: E-GEOD-21508 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

3-indolylacetonitrile decreases Escherichia coli O157:H7 biofilm formation and Pseudomonas aeruginosa virulence.

Lee Jin-Hyung JH Cho Moo Hwan MH Lee Jintae J

Environmental microbiology 20110101 1

Intercellular signal indole and its derivative hydroxyindoles inhibit Escherichia coli biofilm and diminish Pseudomonas aeruginosa virulence. However, indole and bacterial indole derivatives are unstable in the microbial community because they are quickly degraded by diverse bacterial oxygenases. Hence, this work sought to identify novel, non-toxic, stable and potent indole derivatives from plant sources for inhibiting the biofilm formation of E. coli O157:H7 and P. aeruginosa. Here, plant auxin ...[more]

PMID: 20649646

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Dataset Information

The effect of IAN on P. aeruginosa virulence

Publications

3-indolylacetonitrile decreases Escherichia coli O157:H7 biofilm formation and Pseudomonas aeruginosa virulence.

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