Abstract: YLZZ-2 is a strain of Stenotrophomonas maltophilia capable of Swainsonine(SW) degradation.In this study,four condition factors were optimized by orthogonal test including initial culture medium pH,temperature,SW substrate concentration,and speed of shaking.The results show that YLZZ-2 could degrade SW at its best efficiency under the condition of pH value 7.0,temperature 30℃,SW concentration 5%,and shaking speed 160 r·min^-1.Results of resistance test show that the bacteria had ampicillin-and-kanamycin resistance.The resistance disappeared and the ability of SW degradation lost when the plasmids were eliminated from YLZZ-2,which indicates that the SW degradation function of YLZZ-2 is associated with its plasmids.

Key words: Stenotrophomonas maltophilia, Swainsonine, Biodegradation, Degradative plasmid

摘要： YLZZ-2是一种具有降解苦马豆素活性的嗜麦芽寡养单胞菌(Stenotrophomonas maltophilia)。采用正交试验设计对影响其降解能力的培养基初始pH值、温度、底物浓度和摇床转速等4个因素进行优化,以对YLZZ-2的降解特性进行初步了解。结果表明:YLZZ-2菌在pH 7.0,温度30℃,SW添加浓度5%,转速160 r·min^-1时具有最佳降解SW能力。抗性检测表明,该菌具有氨苄青霉素、卡那霉素双重抗性,质粒消除后抗性消失,降解性也丧失,说明YLZZ-2菌降解SW的功能与质粒相关。

关键词: 嗜麦芽寡养单胞菌, 苦马豆素, 生物降解, 降解质粒