降解DBP菌株CQ0302的分离鉴定及其降解特性

Studies on isolation, identification and degradation characteristics of DBP-degradation strain CQ0302

从垃圾填埋场的土壤中分离到一株降解邻苯二甲酸二丁酯(DBP)的细菌CQ0302.经过对其形态特征、生理生化以及16S rRNA序列分析,该菌株初步鉴定为深红红球菌(Rhodococcus ruber).该细菌利用DBP生长的最适温度为30.0～35.0℃,最适pH值为7.0～8.5. DBP浓度低于1500mg/L时的降解动力学方程为ln C=-0.02735t+A,半衰期为25.34h.菌株全细胞蛋白SDS-聚丙烯酰胺电泳结果显示,菌株在DBP诱导前后的全细胞蛋白组成有明显的差异.测定了降解途径中相关酶的活性,表明芳环的裂解是由邻苯二酚1,2-双加氧酶催化的.

A di-n-butyl phthalate (DBP) degradation strain CQ0302 was isolated from rubbish landfill soil. According the morphological characteristics, biophysical biochemical and serial analyses of 16S rDNA, the strain was identified preliminarily as Rhodococcus ruber. The optimal temperature and pH were 30.0-35.0°C and 7.0-8.0 respectively in utilization of DBP by the strain for growing. The degradation dynamic equation was In C = -0.02735t + A when DBP concentration was lower than 1500 mg/L, with half life of 25.34 h. The results of strain wholecell protein SDS-polyacrylamid electrophoresis showed that there were very obvious differences of the total cell protein composition of the strain before and after DBP inducing. The activities of relative enzyme in the degradation process were determined showing that the aromatizing cracking was from the catalysis of catechol 1,2-dioxygenase.