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从辽河口石油污染土壤中筛选到一株能够以2-羟基吡啶作为唯一碳源、氮源和能源进行生长的菌株2PR,基于形态学观察、16S rRNA基因序列分析鉴定菌株2PR属于节杆菌属(Arthrobacter)。菌株2PR生长和降解2-羟基吡啶的最适条件是30℃,pH为7.0。当2-羟基吡啶初始浓度为6.0mg/ml时,120h菌株2PR对2-羟基吡啶的降解效率为94.48%,初始2-羟基吡啶浓度为8.0mg/ml时,156h的降解效率为89.21%。对2-羟基吡啶降解动力学过程进行模拟,结果显示菌株2PR生长和降解过程符合logisitic模型,该模型为环境中2-羟基吡啶的生物降解提供了理论参考。休止细胞反应和中间代谢产物检测表明,菌株2PR在降解2-羟基吡啶的过程中生成了蓝色化合物4,5,4’,5’-tetrahydroxy-3,3’-diazadiphenoquinone-(2,2’)。推测该菌株降解2-羟基吡啶的途径可能是首先由双加氧酶催化生成2,3,6-三羟基吡啶,后者会自发形成蓝色中间代谢产物,2,3,6-三羟基吡啶发生开环反应,最终被完全降解。菌株2PR是已报道菌株中2-羟基吡啶耐受能力和降解能力最强的菌株,在污染物生物修复方面具有广阔的应用前景。
A strain of 2PR which can grow with 2-hydroxypyridine as sole carbon source, nitrogen source and energy was screened from petroleum contaminated soil in Liaohe Estuary. Based on the morphological observation and 16S rRNA gene sequence analysis, strain 2PR was identified as Arthrobacter Arthrobacter). The optimal conditions for strain 2PR to grow and degrade 2-hydroxypyridine are 30 ° C and pH 7.0. When the initial concentration of 2-hydroxypyridine was 6.0mg / ml, the degradation efficiency of 2-hydroxypyridine by 120h strain was 94.48% and that of initial 2-hydroxypyridine was 8.0mg / ml was 89.21% at 156h. The kinetics of degradation of 2-hydroxypyridine was simulated. The results showed that the growth and degradation of strain 2PR conformed to the logisitic model, which provided a theoretical reference for the biodegradation of 2-hydroxypyridine in the environment. The resting cell reaction and the detection of intermediate metabolites showed that strain 2PR produced blue compounds 4,5,4 ’, 5’-tetrahydroxy-3,3’-diazadiphenoquinone- (2,2’ ). It is speculated that this strain degradation of 2-hydroxypyridine pathway may be first catalyzed by dioxygenase 2,3,6-trihydroxypyridine, which will spontaneously form a blue intermediate metabolite, 2,3,6-trihydroxypyridine A ring-opening reaction took place and eventually was completely degraded. Strain 2PR is the most resistant strain of 2-hydroxypyridine in the reported strain, which has broad application prospects in the bioremediation of pollutants.