Department of Biotechnology, Shivaji University, Kolhapur, India.
Appl Biochem Biotechnol. 2013 Mar;169(5):1467-81. doi: 10.1007/s12010-012-0062-5. Epub 2013 Jan 15.
The objective of the study was to execute mutant bacteria for efficient biodegradation of sulfonated azo dye, Green HE4B (GHE4B). UV irradiation was used to introduce random mutations in Pseudomonas sp. LBC1. Genetic alterations induced by UV irradiation in selected mutant bacteria were confirmed by random amplification of polymorphic DNA technique. The mutant bacteria named as Pseudomonas sp. 1 F reduced the time required for complete degradation of recalcitrant dye GHE4B by 25 % when compared with the wild one. The biodegradation was monitored by UV-Vis spectrophotometric analysis. Activities of enzymes like laccase, lignin peroxidase, veratryl alcohol oxidase, and NADH dichlorophenol indophenol reductase were found to be boosted in mutant bacteria as a consequence of UV-induced mutation. Matrix-assisted laser desorption/ionization-time of flight analysis of differentially expressed proteins of mutant bacteria suggested active role of antioxidant enzymes in the degradation of the dye. The degradation product was analyzed by Fourier transform infrared spectroscopy, high-performance thin-layer chromatography, and gas chromatography-mass spectrometry. Results revealed few variations in the degradation end products of wild-type and mutant bacteria. Phytotoxicity study underlined the safer biodegradation of GHE4B by mutant Pseudomonas sp. 1 F.
本研究的目的是利用突变细菌对磺化偶氮染料绿 HE4B（GHE4B）进行有效生物降解。采用紫外线照射的方法在假单胞菌 LBC1 中引入随机突变。通过随机扩增多态性 DNA 技术确认了紫外线照射在选定突变细菌中引起的遗传变化。与野生菌相比，名为假单胞菌 1F 的突变菌将难降解染料 GHE4B 完全降解所需的时间缩短了 25%。通过紫外可见分光光度法分析监测生物降解。结果表明，由于紫外线诱导的突变，突变菌中的漆酶、木质素过氧化物酶、藜芦醇氧化酶和 NADH 二氯酚靛酚还原酶等酶的活性得到了增强。突变菌差异表达蛋白的基质辅助激光解吸/电离飞行时间分析表明，抗氧化酶在染料降解中起重要作用。通过傅里叶变换红外光谱、高效薄层色谱和气相色谱-质谱分析对降解产物进行了分析。结果表明，野生型和突变菌的降解终产物几乎没有差异。植物毒性研究强调了突变假单胞菌 1F 对 GHE4B 的生物降解更安全。
