三株菲降解细菌的分离、鉴定及降解特性的研究

从石油污染土壤中分离纯化到 3株能以菲为唯一碳源和能源生长的革兰氏阴性杆菌、好氧、不形成芽孢、端生或侧生单根鞭毛 ,分别命名为菌株ZX4、ZX6和EVA17.据部分片段长度的 16SrDNA序列比对分析和生理生化试验结果 ,确认此 3株菌均为鞘氨醇单胞菌属 (Sphingomonas)细菌 ,菌株ZX4为少动鞘氨醇单胞菌 (S .paucimobilis) ,菌株ZX6为溶芳烃鞘氨醇单胞菌 (S .aromaticivorans) ,菌株EVA17尚不能确定 .分析了各菌株在系统发育中的分类地位 .菌株ZX4在 14d内对含量为 10 0 0mg·L-1的菲降解率可达 98 74%.不同底物实验结果表明 ,菌株EVA17可能同时拥有两条菲降解途径 .

Isolation, identification and degradation characteristics of three phenanthrene-degrading bacteria

Three bacterial strains capable of utilizing phenanthrene as sole carbon and energy sources were isolated from oil-contaminated soils. All of them were Gram-negative, aerobic, non-spore-forming, polar or side single flagellum rods and named strain ZX4, ZX6 and EVA17, respectively. They were considered to be belonged to Sphingomonas, strain ZX4 as S. paucimobilis, strain ZX6 as S. aromaticivorans and strain EVA17 was not identified to species, based on the results of physio-biochemical identification and the phylogenetical analyses of 16S rDNA sequence. The phylogenetic positions of the 3 strains were performed. The degradation rate of phenanthrene(1 000mg·L^-1) by strain ZX4 was 98.74% within 14 d. Strain EVA17 had two types of metabolism pathway possibly showed by the degradation experiments of different substrates.