阿特拉津降解菌MSD6鉴定及其降解特性研究

Identification and Characterization of Atrazine-degrading Bacterial Strain MSD6

阿特拉津是一种高效除草剂,但其广泛大量的使用对生态环境和人类健康造成了危害。研究采用富集法从黑龙江省南部长期施用阿特拉津玉米田土壤中分离到一株能降解阿特拉津的菌株MSD6,通过生理生化和16S rRNA序列分析,确定菌株MSD6为节杆菌属(Arthrobacter sp.),该菌株16S rRNA序列GenBank登录号为MH698840。菌株MSD6在48h对阿特拉津的降解率可达到90%以上。菌株MSD6对碱性环境适应性较好,在pH为9的条件下生长OD600值为0.486,对阿特拉津的降解率为30.89%。该菌株也显示出对NaCl胁迫有较好耐性,在4%NaCl胁迫下,其生长量OD600值为0.455,阿特拉津降解率为43.91%。菌株对高温环境适应性相对较差。菌株MSD6生长和降解阿特拉津的适宜pH为6～7,最适温度为30℃。

Atrazine is a highly effective herbicide, but its widespread use poses a threat to the ecological environment and human health. An atrazine-degrading strain MSD6 was isolated from the soil of maize fields in southem Heilongjiang Province. The strain MSD6 was identified as Arthrobacter sp by physiological, biochemical and 16S rRNA sequence analysis. The 16S rRNA sequence GenBank login number of the strain was MH698840. The degradation rate of strain MSD6 in atrazine at 48h can reach more than 90%. The strain MSD6 was well adapted to alkaline environment. The growth OD600 value and the degradation rate of atrazine were 0.486 and 30.89% at pH 9, respectively. The strain also showed better tolerance to NaCl stress. Under 4% NaC1 stress, its growth OD600 value was 0.455, and the degradation rate of atrazine was 43.91%. The adaptability of strain to high temperature environment is relatively poor. The optimum pH for growth and degradation of atrazine by strain MSD6 was 6-7 and the optimum temperature was 30℃.