Department of Pesticide Science, Hunan Agricultural University, 410128, Changsha, People's Republic of China.
Folia Microbiol (Praha). 2012 Mar;57(2):139-47. doi: 10.1007/s12223-012-0107-8. Epub 2012 Mar 3.
The pyrazosulfuron-ethyl-degrading bacterium, designated as CW17, was isolated from contaminated soil near the warehouse of the factory producing pyrazosulfuron-ethyl in Changsha city, China. The strain CW17 was identified as Acinetobacter sp. based on analyses of 94 carbon source utilization or chemical sensitivity in Biolog microplates, conventional phenotypic characteristics, and 16S rRNA gene sequencing. When pyrazosulfuron-ethyl was provided as the sole carbon source, the effects of pyrazosulfuron-ethyl concentration, pH, and temperature on biodegradation were examined. The degradation rates of pyrazosulfuron-ethyl at initial concentrations of 5.0, 20.0, and 50.0 mg/L were 48.0%, 77.0%, and 32.6%, respectively, after inoculation for 7 days. The growth of the strain was inhibited at low pH buffers. The chemical degradation occurs much faster at low pH than at neutral and basic pH conditions. The degradation rate of pyrazosulfuron-ethyl at 30°C was faster than those at 20 and 37°C by CW17 strains. Two metabolites of degradation were analyzed by liquid chromatography-mass spectroscopy (LC/MS). Based on the identified products, strain CW17 seemed to be able to degrade pyrazosulfuron-ethyl by cleavage of the sulfonylurea bridge.
从中国长沙市生产吡唑磺隆乙基的工厂仓库附近污染土壤中分离到一株能够降解吡唑磺隆乙基的细菌，命名为 CW17。根据 Biolog 微孔板上 94 种碳源利用或化学敏感性分析、常规表型特征和 16S rRNA 基因测序，将菌株 CW17 鉴定为不动杆菌属。当吡唑磺隆乙基作为唯一碳源时，考察了吡唑磺隆乙基浓度、pH 值和温度对生物降解的影响。接种 7 天后，初始浓度为 5.0、20.0 和 50.0mg/L 的吡唑磺隆乙基的降解率分别为 48.0%、77.0%和 32.6%。该菌株在低 pH 缓冲液中生长受到抑制。在低 pH 条件下，化学降解比中性和碱性 pH 条件下快得多。CW17 菌株在 30°C 时的降解速率比在 20°C 和 37°C 时快。通过液相色谱-质谱（LC/MS）分析了两种降解代谢物。根据鉴定出的产物，菌株 CW17 似乎能够通过磺酰脲桥的断裂来降解吡唑磺隆乙基。
