Huang Xing, Zhang Hao, Chen Feng, Song Man
College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.
Curr Microbiol. 2018 Feb;75(2):156-162. doi: 10.1007/s00284-017-1360-5. Epub 2017 Sep 22.
Strain QCT6, capable of degrading metribuzin, was isolated from metribuzin-contaminated soil. The isolate was identified as Paracoccus sp. according to its physiological characteristics, biochemical tests, and 16S rRNA gene phylogenetic analysis. In liquid culture, 86.4% of 50 mg/L metribuzin was removed by strain QCT6 after incubation for 7 days. The product of metribuzin degradation by QCT6 was identified as deamino-metribuzin, which has reduced phytotoxicity on the growth of maize. After being marked with the gfp gene, the colonization and distribution of gfp-tagged QCT6 were directly observed with a confocal laser scanning microscope. The QCT6 strain showed good colonization ability on maize roots and was maintained for at least 20 days in rhizosphere soil. After root irrigation with gfp-tagged QCT6, 75.7% of 15 mg/L metribuzin was removed from the maize rhizosphere soil. This metribuzin-degrading strain QCT6 has strong potential applications for in situ bioremediation of soil contaminated with metribuzin.
从嗪草酮污染土壤中分离出能够降解嗪草酮的菌株QCT6。根据其生理特征、生化试验及16S rRNA基因系统发育分析，该分离菌株被鉴定为副球菌属（Paracoccus sp.）。在液体培养中，菌株QCT6在培养7天后可去除50mg/L嗪草酮中的86.4%。QCT6降解嗪草酮的产物被鉴定为脱氨基嗪草酮，其对玉米生长的植物毒性降低。用绿色荧光蛋白（gfp）基因标记后，利用共聚焦激光扫描显微镜直接观察gfp标记的QCT6的定殖和分布情况。QCT6菌株在玉米根上表现出良好的定殖能力，在根际土壤中可维持至少20天。用gfp标记的QCT6进行根灌后，从玉米根际土壤中去除了15mg/L嗪草酮中的75.7%。这种降解嗪草酮的菌株QCT6在原位生物修复被嗪草酮污染的土壤方面具有很强的潜在应用价值。
