细菌化学诱变育种对富钾砂页岩生物浸矿提钾的影响  

Effects of chemical mutation on bacterial extracting potassium from potassium-rich sandshale

作　　者：周德志[1] 陈晔[1,2] 曹飞[1,2] 孙德四[1] 

机构地区：[1]九江学院化学与环境工程学院,九江332005 [2]九江学院生命科学学院,九江332005

出　　处：《中国有色金属学报》2015年第3期824-833,共10页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(51264014;31360064);江西省教育厅科技项目(GJJ14736)

摘　　要：以多黏芽孢杆菌P.Polymyxa(PA)和根瘤农杆菌A.tumefaciens(AT)为出发菌株,采用硫酸二乙酯(DES)对其进行诱变育种与浸矿研究。结果表明:分别通过30和40 mg/L的DES处理出发菌株PA和AT,致死率分别为87%和85%,正突变率分别为10%和16%;筛选获得的两株突变菌PAM和ATM达到生长稳定期的时间分别比对应的出发菌株缩短了48和24 h,且具有更大的菌体密度以及产酸和产蛋白质与多糖的能力;浸出15 d,诱变菌株PAM和ATM从富钾砂页岩中释放的K2O量分别比对应的出发菌株提高了29.00%和21.28%,且达到浸出终点的时间分别提前了5和3 d;混合诱变菌株浸出的K2O的量比单一诱变菌株PAM和ATM浸出的K2O的量分别提高了22.78%和67.55%,且达到浸出终点的时间比出发菌株的提前了6 d;SEM和XRD分析结果表明:混合诱变菌株对富钾砂页岩的破坏作用最为明显;在富钾页岩混合菌浸矿过程中,P·Polymyxa为浸矿优势菌种,诱变前后混合菌浸出15 d后,P.Polymyxa和A.tumefaciens的菌落个数比由最初的1:1分别变为7:1和18:1。The P.Polymyxa(PA) and A.tumefaciens(AT) were used as original strains, and the mutagenesis and bioleaching induced by diethylsulfate(DES) were studied. The results show that the lethal rates of the original strains PA and AT are 87% and 85%, and the positive mutant rates are 10% and 16% after being treated by 30 and 40 mg/L DES, respectively. The two mutants of P.Polymyxa(PAM) and A.tumefaciens(ATM) screened from positive mutant strains reach stationary stages 48 h and 24 h, respectively, ahead of the corresponding original strains. PAM and ATM have higher bacterial concentrations and higher producing ability of organic acids, polysaccharides and proteins, than those of the original strains. After a 15 d leaching, the K2 O concentrations in supernatants of the mutant stains PAM and ATM are improved by 29.00% and 21.28%. And the mutant strains PAM and ATM can shorten the leaching time by 5 d and 3 d, respectively, than those of the two corresponding original strains. After bioleaching for 15 d with the mixture of the two mutant strains PAM and ATM, the K2O concentration of the supernatant is 22.78% and 67.55% higher than that with the single mutant strain PAM or ATM, respectively, and the mixture can shorten leaching time by 6 d in comparison with the original strains. The SEM and XRD analyses of potassium-rich shale surfaces before and after leaching show that the mixture of PAM and ATM has the greatest corrosion and decomposition ability on shale. P.Polymyxa is the dominant culture in bacterial community during bioleaching of potassium-rich shale. After bioleaching for 15 d, the proportion of cell density in the supernatants of P.Polymyxa and A.tumefaciens before and after DES-induced mutagenesis is changed from 1:1 to about 7:1 and 18:1, respectively.

关 键 词：“钾”细菌 诱变 硫酸二乙酯 细菌浸出 提钾 富钾砂页岩 

分 类 号：Q93[生物学—微生物学]