PMID- 12765878 OWN - NLM STAT- MEDLINE DCOM- 20030924 LR - 20200930 IS - 1040-0605 (Print) IS - 1040-0605 (Linking) VI - 285 IP - 3 DP - 2003 Sep TI - Phenazine-1-carboxylic acid, a secondary metabolite of Pseudomonas aeruginosa, alters expression of immunomodulatory proteins by human airway epithelial cells. PG - L584-92 AB - Pseudomonas aeruginosa is a gram-negative bacterium that causes both acute and chronic lung disease in susceptible patient populations. P. aeruginosa secretes numerous proteins and secondary metabolites, many of which have biological effects that likely contribute to disease pathogenesis. An unidentified small-molecular-weight factor was previously reported to increase IL-8 release both in vitro and in vivo. To identify this factor, we subjected the <3-kDa fraction from P. aeruginosa-conditioned medium to HPLC analysis. A peak fraction that stimulated IL-8 release was found by mass spectrometry to have a molecular mass (MM) of 224 Da. On the basis of this MM and other biochemical properties, we hypothesized that the factor was phenazine-1-carboxylic acid (PCA). Subsequent studies and comparison with purified PCA confirmed this hypothesis. Purified PCA exhibited a number of biological effects in human airway epithelial cells, including increasing IL-8 release and ICAM-1 expression, as well as decreasing RANTES and monocyte chemoattractant protein-1 (MCP-1) release. PCA also increased intracellular oxidant formation as measured by electron paramagnetic resonance and by an intracellular oxidant-sensitive probe. Antioxidants inhibited PCA-dependent increases in IL-8 and ICAM-1, suggesting that oxidants contributed to these effects. However, in contrast to the related phenazine compound pyocyanin, PCA did not oxidize NAD(P)H at physiologically relevant pH, providing preliminary evidence that PCA and pyocyanin may have distinct redox chemistries within the cell. Thus PCA is a biologically active factor secreted by P. aeruginosa that has several activities that could alter the host immune and inflammatory response and thereby contribute to bacterial disease pathogenesis. FAU - Denning, Gerene M AU - Denning GM AD - Department of Internal Medicine, University of Iowa, Iowa City 52242, USA. gerene-denning@uiowa.edu FAU - Iyer, Shankar S AU - Iyer SS FAU - Reszka, Krzysztof J AU - Reszka KJ FAU - O'Malley, Yunxia AU - O'Malley Y FAU - Rasmussen, George T AU - Rasmussen GT FAU - Britigan, Bradley E AU - Britigan BE LA - eng GR - AI-34954-04/AI/NIAID NIH HHS/United States PT - Journal Article PT - Research Support, Non-U.S. Gov't PT - Research Support, U.S. Gov't, Non-P.H.S. PT - Research Support, U.S. Gov't, P.H.S. DEP - 20030523 PL - United States TA - Am J Physiol Lung Cell Mol Physiol JT - American journal of physiology. Lung cellular and molecular physiology JID - 100901229 RN - 0 (Adjuvants, Immunologic) RN - 0 (Antioxidants) RN - 0 (Chemokine CCL2) RN - 0 (Chemokine CCL5) RN - 0 (Culture Media, Conditioned) RN - 0 (Phenazines) RN - 0 (Reactive Oxygen Species) RN - 126547-89-5 (Intercellular Adhesion Molecule-1) RN - 2538-68-3 (1-phenazinecarboxylic acid) RN - 53-59-8 (NADP) SB - IM MH - Adjuvants, Immunologic/metabolism MH - Antioxidants/pharmacology MH - Cells, Cultured MH - Chemokine CCL2/metabolism MH - Chemokine CCL5/metabolism MH - Chromatography, High Pressure Liquid MH - Culture Media, Conditioned/pharmacology MH - Electron Spin Resonance Spectroscopy MH - Humans MH - Intercellular Adhesion Molecule-1/metabolism MH - NADP/metabolism MH - Oxidation-Reduction MH - Phenazines/chemistry/isolation & purification/*pharmacology MH - Pseudomonas Infections/*immunology/metabolism MH - Pseudomonas aeruginosa/*chemistry/metabolism MH - Reactive Oxygen Species/metabolism MH - Respiratory Mucosa/cytology/*immunology/microbiology EDAT- 2003/05/27 05:00 MHDA- 2003/09/25 05:00 CRDT- 2003/05/27 05:00 PHST- 2003/05/27 05:00 [pubmed] PHST- 2003/09/25 05:00 [medline] PHST- 2003/05/27 05:00 [entrez] AID - 00086.2003 [pii] AID - 10.1152/ajplung.00086.2003 [doi] PST - ppublish SO - Am J Physiol Lung Cell Mol Physiol. 2003 Sep;285(3):L584-92. doi: 10.1152/ajplung.00086.2003. Epub 2003 May 23.