拟无枝菌酸菌M3-1降解丙酯草醚的特性及应用初探

丙酯草醚是我国自主研制的一种新型高效油菜田除草剂。采用现代分子生物技术和微生物学传统方法从长期施用嘧啶水杨酸类除草剂的农田中富集、筛选出以丙酯草醚为唯一碳源生长的高效降解菌株M3-1,并对其最适降解条件及在土壤中的应用进行研究。结果表明:(1)经形态、生理生化和16S rDNA鉴定,M3-1属于拟无枝菌酸菌(Amycolatopsis sp.)。(2)最适温度为35℃,pH为6.0,接种量为8%,在底物(ZJ0273)浓度为100～400 mg.L.1均具有一定的降解效果,且降解率随底物浓度的增加而降低,浓度高于300 mg.L.1时,对M3-1的降解效果有较强的抑制作用。(3)最适降解条件下,水溶液中培养25 d对浓度为100 mg.L.1丙酯草醚的降解率可达63.3%。(4)M3-1在土壤中对ZJ0273有很好的去除效果,处理25 d,其降解率可达53.7%。

Degradation Characteristics and Applications of Amycolatopsis sp.M3-1 for ZJ0273

ZJ0273,Propyl 4-(2-(4,6-dimethoxypyrimidin-2-yloxy) benzylamino) benzoate,is a novel herbicide with the property of high activity,broad spectrum and low toxicity to animals,and it is developed for pre-and post-emergence weed control in the oilseed rape field.The highly efficient ZJ0273 degrading bacterial strain M3-1 was screened,isolated and separated from farmland of long-term using pyrimidinylthiobenzoate herbicides by applying modern molecular biological techniques together with the traditional microbiological methods,and it can grow on by using ZJ0273 as the sole carbon and energy source.The strain M3-1 was identified as Amycolatopsis sp.by physiological,biochemical tests and 16s rDNA sequence.The optimum ZJ0273 degrading conditions of using strain M3-1 and their application in soil were studied.The results show that with condition of 35℃,pH 6.0,8% of inoculation and 100 mg?L?1 of ZJ0273,the degrading ratio in 25 d is 63.3%.Using strain M3-1,the degradation ratio of ZJ0273 is decreased with the increasing ZJ0273 concentration;300 mg?L?1 of ZJ0273 can strongly inhibit bio-activity of strain M3-1,which means that higher concentration of ZJ0273 has higher toxicity to M3-1.The strain M3-1also has a good degradation effect to ZJ0273 in soil,the degradation ratio could up to 53.7% after 25 days.The physicochemical properties of strain M3-1 may open new possibilities for its biotechnological applications and allow the use of Amycolatopsis sp.M3-1 in the soil bioremediation.