Genomic damage induced in tobacco plants by chlorobenzoic acids—Metabolic products of polychlorinated biphenyls

0322266 - ÚEB 2009 RIV NL eng J - Journal Article
Gichner, Tomáš - Lovecka, P. - Vrchotová, B.
Genomic damage induced in tobacco plants by chlorobenzoic acids—Metabolic products of polychlorinated biphenyls.
[Poškození genomu rostlin tabáku indukované chlorbenzoovými kyselinami - Metabolické produkty polychlorovaných bifenylů.]
Mutation Research - Genetic Toxicology and Environmental Mutagenesis. Roč. 657, č. 2 (2008), s. 140-145. ISSN 1383-5718. E-ISSN 1879-3592
R&D Projects: GA ČR GA521/05/0500; GA ČR GA203/06/0563
Institutional research plan: CEZ:AV0Z50380511
Keywords : Comet assay * Delor 103 * Ethyl methanesulphonate
Subject RIV: EB - Genetics ; Molecular Biology
Impact factor: 2.363, year: 2008

Tobacco seedlings (Nicotiana tabacum var. xanthi) were treated for 24 h with mono-(2- and 3-CBA), di-(2,5- and 3,4-CBA), and tri-(2,4,6- and 2,3,5-CBA)-chlorobenzoic acids (CBAs) and with the mixture of polychlorinated biphenyls – Delor 103, or cultivated for 1 or 2 weeks in soil polluted with the CBAs. DNA damage in nuclei of leaves and roots was evaluated by the comet assay. A significant increase in DNA damage was observed only at concentrations of CBAs that caused withering of leaves or had lethal effects within 2–4 weeks after the treatments. As the application of CBAs did not induce somatic mutations, the induced DNA migration is probably caused by necrotic DNA fragmentation and not by DNA damage resulting in genetic alteration. In contrast, the application of the monofunctional alkylating agent ethyl methanesulphonate as a positive control resulted in a dose–response increase of DNA damage and an increase of somatic mutations. Thus, the EMS-produced DNA migration is probably associated with genotoxin-induced DNA fragmentation. The data demonstrate that the comet assay in plants should be conducted together with toxicity studies to distinguish between necrotic and genotoxin-induced DNA fragmentation. The content of 2,5-CBA in tobacco seedlings was measured by reverse-phase high pressure liquid chromatography.

Chlorobenzové kyseliny (CBAs) vznikaji v pudě kontaminovane polycyklickými bifenyly (PCB) v důsledku metabolizace PCB pudními mikroorganismy. Po aplikaci mono-, di- a tri CBAs na semenáčky tabáku bylo prokázáno kometovým testem silné poškození DNA. Toto poškození bylo prokázáno jen u dávek CBAs, které vyvolávají silné toxické a letální účinky. Indukce somatických mutací po aplikaci CBAs nebylo prokázáno. Fragmentace DNA po aplikaci CBAs je tedy způsobeno nekrotickým poškozením DNA a ne v důsledku genotoxicity.
Permanent Link: http://hdl.handle.net/11104/0170581