Transgenic tobacco plants expressing atzA exhibit resistance and strong ability to degrade atrazine

Abstract

Atrazine chlorohydrolase (AtzA) catalyzes hydrolytic dechlorination and can be used in detoxification of atrazine, a herbicide widely employed in the control of broadleaf weeds. In this study, to investigate the potential use of transgenic tobacco plants for phytoremediation of atrazine, atzA genes from Pseudomonas sp. strain ADP and Arthrobacter strain AD1 were transferred into tobacco. Three and four transgenic lines, expressing atzA-ADP and atzA-AD1, respectively, were produced by Agrobacterium-mediated transformation. Molecular characterization including PCR, RT-PCR and Southern blot revealed that atzA was inserted into the tobacco genome and stably inherited by and expressed in the progenies. Seeds of the T(1) transgenic lines had a higher germination percentage and longer roots than the untransformed plants in the presence of 40-150 mg/l atrazine. The T(2) transgenic lines grew taller, gained more dry biomass, and had higher total chlorophyll content than the untransformed plants after growing in soil containing 1 or 2 mg/kg atrazine for 90 days. No atrazine residue remained in the soil in which the T(2) transgenic lines were grown (except 401), while, in the case of the untransformed plants, 0.91 mg (81.3%) and 1.66 mg (74.1%) of the atrazine still remained in the soil containing 1 and 2 mg/kg of atrazine, respectively, indicating that the transgenic lines could degrade atrazine effectively. The transgenic tobacco lines developed could be useful for phytoremediation of atrazine-contaminated soil and water.

Degrading and Phytoextracting Atrazine Residues in Rice (Oryza sativa) and Growth Media Intensified by a Phase II Mechanism Modulator

“…To fortify toxicant uptake and degradation in plants, efforts have been made to express microbial catabolic enzymes in target plants. 16,17 The transformation of plants carrying a mammalian liver P450s (cytochrome P450 monooxygenases) CYP1A1 was reported to degrade herbicides chlorotoluron and norflurazon in potato plants. 18 Plants are naturally gifted with multiple mechanisms for eliminating organic xenobiotics through enzymatic and nonenzymatic degrading systems.…”

“…In this way, selection of desirable plants is essential for the proposed goal achievement. To fortify toxicant uptake and degradation in plants, efforts have been made to express microbial catabolic enzymes in target plants. , The transformation of plants carrying a mammalian liver P450s (cytochrome P450 monooxygenases) CYP1A1 was reported to degrade herbicides chlorotoluron and norflurazon in potato plants …”

Evaluation of the Agronomic Performance of Atrazine-Tolerant Transgenic japonica Rice Parental Lines for Utilization in Hybrid Seed Production

“…Genomic DNA was isolated from young leaves using a modified CTAB method [19] . PCR was performed to preliminarily select the transformed plants using primers atzA7/atzA8 [20] and SL-Ubi-C-F/SL-Ubi-C-R ( Table 1 ). RT-PCR was performed to further confirm the expression of atzA in the PCR-positive transformed plants.…”

“…cDNA was synthesized using atzA8 and oligo(dT) as primers and SuperScript™ II RNase H− (Invitrogen) as reverse transcriptase. RT-PCR was amplified using the cDNA as template and atzA7/atzA2 [20] as primers. β -actin (AB047313) was also amplified as the internal control using actin-R/actin-F as primers [21] .…”

Alfalfa (Medicago Sativa L.): Genotypic Diversity and Transgenic Alfalfa for Phytoremediation

“…Besides transgenic alfalfa plants, transgenic tobacco expressing Pseudomonas sp. atzA (Wang et al, 2010), transgenic rice (Oryza sativa) (Inui and Ohkawa 2005;Kawahigashi et al, 2005;Kawahigashi et al, 2006;Kawahigashi et al, 2008), and potato (Inui and Ohkawa 2005) expressing human CYP1A1, CYP2B6, or CYP2C19, potato expressing rat CYP1A1 (Yamada et al, 2002), Brassica juncea overexpressing Brassica juncea γ-Glutamycysteine synthetase (γ-ECS, GS) gene, and Nicotiana tabaccum and Medicago sativa expressing p-atzAa gene (Wang et al, 2005) were used for the phytoremediation of atrazine and other herbicides, insecticides, and industrial chemicals.…”