School of Biosciences, Mahatma Gandhi University, Kottayam, Kerala, India.
Bull Environ Contam Toxicol. 2011 Jan;86(1):110-3. doi: 10.1007/s00128-010-0162-2. Epub 2010 Dec 9.
Sodium dodecyl sulphate (SDS), an anionic surfactant, has been used extensively due to its low cost and excellent foaming properties. Fifteen different bacterial isolates capable of degrading SDS were isolated from detergent contaminated soil by enrichment culture technique and the degradation efficiency was assessed by Methylene Blue Active Substances (MBAS) assay. The most efficient SDS degrading isolate was selected and identified as Pseudomonas aeruginosa S7. The selected isolate was found to harbor a single 6-kb plasmid. Acridine orange, ethidium bromide, SDS and elevated temperatures of incubation failed to cure the plasmid. The cured derivatives of SDS degrading Pseudomonas aeruginosa were obtained only when ethidium bromide and elevated temperature (40 °C) were used together. Transformation of E. coli DH5α with plasmid isolated from S7 resulted in subsequent growth of the transformants on minimal salt media with SDS (0.1%) as the sole source of carbon. The SDS degradation ability of S7 and the transformant was found to be similar as assessed by Methylene Blue Active Substance Assay. The antibiotic resistance profiles of S7, competent DH5α and transformant were analyzed and it was noted that the transfer of antibiotic resistance correlated with the transfer of plasmid as well as SDS degrading property.
十二烷基硫酸钠（SDS）是一种阴离子表面活性剂，由于其成本低、发泡性能优异而被广泛应用。本研究采用富集培养技术从含洗涤剂污染的土壤中分离出 15 株能够降解 SDS 的细菌，并用亚甲蓝活性物质（MBAS）法评估其降解效率。选择降解 SDS 效率最高的菌株，并将其鉴定为铜绿假单胞菌 S7。该分离株含有一个 6kb 的质粒。吖啶橙、溴化乙锭、SDS 和孵育温度升高均不能消除该质粒。只有当同时使用溴化乙锭和高温（40°C）时，才能得到能降解 SDS 的铜绿假单胞菌的无质粒衍生物。从 S7 中分离的质粒转化 E. coli DH5α 后，转化子能够在含有 SDS（0.1%）作为唯一碳源的基础盐培养基上生长。通过亚甲蓝活性物质法评估，发现 S7 和转化子的 SDS 降解能力相似。分析了 S7、感受态 DH5α 和转化子的抗生素抗性谱，结果表明，抗生素抗性的转移与质粒的转移以及 SDS 降解特性有关。
