title: Antioxidant enzymes expression in Pseudomonas aeruginosa exposed to UV-C radiation.
abstract: It was well known that, UV-C irradiation increase considerably the reactive oxygen species (ROS) levels in eukaryotic and prokaryotic organisms. In the enzymatic ROS-scavenging pathways, superoxide dismutase (SOD), Catalase (CAT), and peroxidase (POX) were developed to deal with oxidative stress. In this study, we investigated the effects of UV-C radiations on antioxidant enzymes (catalase, superoxide dismutase, and peroxidases) expression in Pseudomonas aeruginosa. Catalase, superoxide dismutase, and peroxidases activities were determined spectrophotometrically. Isozymes of superoxide dismutase were revealed by native gel activity staining method. Lipid peroxidation was determined by measuring malondialdehyde formation. Our results showed that superoxide dismutase, catalase and peroxidase activities exhibited a gradual increase during the exposure time (30 min). However, the superoxide dismutase activity was maximized at 15 min. Native gel activity staining assays showed the presence of three superoxide dismutase isozymes. The iron-cofactored isoform activity was altered after exposure to UV-C stress. These finding suggest that catalase and peroxidase enzymes have the same importance toward UV-C rays at shorter and longer exposure times and this may confer additional protection to superoxide dismutase from damage caused by lipid peroxidation. Moreover, our data demonstrate the significant role of the antioxidant system in the resistance of this important human pathogen.
authors.affiliation: Laboratoire de Traitement des Eaux Usées, Centre des Recherches et des Technologies des Eaux (CERTE), Technopole Borj Cedria, Soliman, Tunisie.
authors.forename: Kloula Ben Ghorbal
authors.initials: KB
authors.lastname: Salma
authors.affiliation: Laboratoire de Traitement des Eaux Usées, Centre des Recherches et des Technologies des Eaux (CERTE), Technopole Borj Cedria, Soliman, Tunisie.
authors.forename: Maalej
authors.initials: M
authors.lastname: Lobna
authors.affiliation: Laboratoire de Traitement des Eaux Usées, Centre des Recherches et des Technologies des Eaux (CERTE), Technopole Borj Cedria, Soliman, Tunisie.
authors.forename: Khefacha
authors.initials: K
authors.lastname: Sana
authors.affiliation: Laboratoire de Traitement des Eaux Usées, Centre des Recherches et des Technologies des Eaux (CERTE), Technopole Borj Cedria, Soliman, Tunisie.
authors.forename: Chourabi
authors.initials: C
authors.lastname: Kalthoum
authors.affiliation: Laboratoire des Microorganismes et Biomolécules Actives (LMBA), Faculté des Sciences de Tunis, Campus Universitaire, El Manar II, Tunisie.
authors.forename: Ouzari
authors.initials: O
authors.lastname: Imene
authors.affiliation: Laboratoire de Traitement des Eaux Usées, Centre des Recherches et des Technologies des Eaux (CERTE), Technopole Borj Cedria, Soliman, Tunisie.
authors.forename: Chatti
authors.initials: C
authors.lastname: Abdelwaheb
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D002374:Catalase / Q000378:metabolism*; D015227:Lipid Peroxidation; D008315:Malondialdehyde / Q000378:metabolism*; D018384:Oxidative Stress; D010544:Peroxidases / Q000378:metabolism*; D011550:Pseudomonas aeruginosa / Q000201:enzymology / Q000378:metabolism / Q000528:radiation effects*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism*; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: D000975:Antioxidants; D017382:Reactive Oxygen Species; D008315:Malondialdehyde; D010544:Peroxidases; D002374:Catalase; D013482:Superoxide Dismutase
keywords: Antioxidants enzymes; Malondialdehyde; Pseudomonas; Resistance; UV-C