菌株Cupriavidus sp.DT-1对液体和土壤中TCP的降解

Biodegradation of 3,5,6-trichloro-2-pyridinol by Cupriavidus sp.DT-1 in liquid and soil environments

采用液质联用(HPLC-MS)的方法检测菌株Cupriavidus sp.DT-1降解2-羟基吡啶(2-HP)的代谢产物.并用三亲结合、荧光定量PCR(q-PCR)方法评价降解菌对3,5,6-三氯-2-吡啶酚(TCP)污染土壤的修复效果.结果表明,菌株可以进一步降解2-HP,依次生成尼古丁蓝、马来酰胺酸和反丁烯二酸,直至转化成菌株DT-1生长的碳源.接种菌株DT-1对污染土壤中TCP的降解起到较大的促进作用,2组试验土壤中TCP(50mg/kg)降解率分别为94.4%和86.7%,未接种菌株的土壤中TCP降解率仅为20.4%和28.4%.带有绿色荧光蛋白基因gfp标记的菌株DT-1-gfp可在土壤中存活35d以上,并对TCP污染土壤的细菌群落丰度有显著的恢复作用.

Cupriavidus sp.DT-1 was a 3,5,6-trichloro-2-pyridinol(TCP)-degrading strain which could transform TCP to 2-hydroxypyridine(2-HP).Liquid-mass spectrometry(HPLC-MS)was used to detect the degradation products of 2-HP,And the methods of triparetal conjugation,quantitative real-time PCR(q-PCR)were used to evaluate the remediation effect of TCP-contaminated soils by the degrading-bacterium.Results showed that strain DT-1 was able to further degrade 2-HP,and sequentially produced nicotine blue,maleamic acid and fumaric acid,until it was transformed into the carbon source that could support the growth of strain DT-1.Pilot experiment showed that inoculation of strain DT-1 remarkably accelerated the elimination of TCP in soils.The degradation rates of TCP in inoculated soils were 94.4%and 86.7%,while those in uninoculated soils were 20.4%and 28.4%,respectively.Green fluorescent protein encoding gene gfp harbored strain DT-1-gfp could survive in soils for more than 35d.The results of q-PCR showed that inoculation of strain DT-1-gfp significantly improved the recovery of bacterial community abundance in the TCP-contaminated soils.