一株Diaphorobacter属细菌对苯酚的降解特性和代谢途径

Diaphorobacter sp.ZW12菌株具有较高的苯酚耐受性和降解能力,通过摇瓶培养在以苯酚为唯一碳源的基本培养基中考察该菌株对苯酚的耐受性和苯酚降解特性。结果表明,该菌株能在苯酚浓度为4.0g/L的培养基中生长,完全降解苯酚的最高浓度可达3.0g/L。其最适生长pH、生长温度和代谢温度分别是pH7.0、33℃和30℃。利用苯酚羟化酶基因(Lph)、邻苯二酚-1,2-加氧酶基因(C12O)和邻苯二酚-2,3-加氧酶基因(C23O)特异性引物对ZW12总DNA进行PCR扩增,结果Lph基因和C23O基因PCR扩增阳性、C12O基因扩增呈阴性,表明ZW12对苯酚的代谢是通过C23O途径进行的。

Characteristics and Pathway of Phenol Decomposing for a Strain of Diaphorobacter

Phenol tolerance and decomposing characteristics of Diaphorobacter sp.ZW12 using phenol as sole carbon source in minimal medium by flask culture were studied.Results showed that ZW12 could grow in medium with 4.0g/L phenol,and phenol could be decomposed completely when phenol concentration was 3.0g/L.Its optimum growth pH and temperature were 7.0 and 33℃ respectively,while its optimum metabolic temperature was 30℃.Phenol hydorxylase gene(Lph),catachol-1,2-dioxygenase gene (C12O)andcatachol2,3-dioxygenasegene(C23O)weredetectedbyPCRamplificationfromtotalDNA.PCR amplification ofLph and C23O gene were positive,while that of C12O gene was negative,which showed that phenol were decomposed by ZW12 through C23O pathway.