苯酚降解菌TX1的分离鉴定及其降解特性

Isolation,Identification and Characterization of Phenol-Degrading Strain Trichosporon sp.TX1

从受酚类污染的土壤中分离筛选出1株能够高效降解苯酚的菌株。通过形态学、生理生化以及26S核糖体（rDNA）测序等手段对其进行初步鉴定，确定该菌株为丝孢酵母菌属（Trichosporon sp．），命名为TX1。初步研究结果表明，该菌株对苯酚的代谢途径为将苯酚先转化为邻苯二酚的苯酚羟化酶定位于细胞膜和细胞质；进而通过邻苯二酚1，2-双加氧酶（C120）邻位开环裂解，C120为诱导型胞内酶。通过分批培养得到菌株TX1降解苯酚的生长动力学模型可用霍尔丹（Haldane）方程表述，相关参数μmax=0．667h^-1，Ks=51．14mg／L，Ki=271．7mg／L。

An effective phenol-degrading yeast strain was isolated from phenol-contaminated soil. According to morphological, physiological, 26S rDNA gene sequencing, and etc. means, the strain was identified as genus Trichosporon sp. named TX1. The preliminary study on the metabolic pathway of phenol about this strain indicated that the phenol hydroxylase in the cell membrane and cytoplasm had transformed phenol into catechol first; and then ortho-open aromatic ring cleavage was carried out with catechol 1,2-dioxygenase （C120）, an inducible intracellular enzyme. With the data obtained in batch culture of the strain TX1, its growth kinetics model of the degradation of phenol could be fitted with Haldane equation, and the related parameters of μmax, Ks and Ki were 0.667 h^-1 1, 51.14 mg/L and 271.7 mg/L, respectively.