摘要： 为探明耐铬（Ⅲ）油菜内生菌BNC-Q菌株对铬（Ⅲ）处理的生理生化反应性特点，以BNC-Q菌株为研究对象，进行了菌种鉴定以及铬（Ⅲ）处理反应性分析等试验。16S rDNA PCR分析结果表明，BNC-Q菌株为阿氏芽孢杆菌。铬（Ⅲ）胁迫培养试验结果表明，BNC-Q对铬（Ⅲ）耐受较强，可在5 mmol/L铬（Ⅲ）浓度条件下保持繁殖能力，可被不高于2 mmol/L的铬（Ⅲ）促进生长繁殖。蛋白质表达分析试验结果表明，经2 mmol/L铬（Ⅲ）处理后，BNC-Q可特异表达出一条约40 ku大小的蛋白质条带。抗氧化性分析试验结果表明，2 mmol/L铬（Ⅲ）处理对BNC-Q菌株清除DPPH自由基的能力基本无影响，但其对超氧阴离子自由基（O₂^-·）和羟基自由基（·OH）的清除率分别由63.7%，63.5%上升到91.1%，85.2%。综上所述，BNC-Q菌株为阿氏芽孢杆菌，对铬（Ⅲ）耐受性较强，可被铬（Ⅲ）诱导表达约40 ku的特异蛋白，铬（Ⅲ）诱导处理可显著提高其清除超氧阴离子自由基和羟基自由基的能力。研究结果可为重金属铬的生物修复研究提供一定的基础。

关键词: 油菜, 阿氏芽孢杆菌, 耐铬(Ⅲ), SDS-PAGE, 抗氧化性

Abstract: In order to verify the characteristics of physiological and biochemical response to Cr(Ⅲ), the chromium(Ⅲ)-resistant endophytic bacterium strain BNC-Q, which was isolated from Brassica napus L.in previous research, has been identified and been studied for its reactivity to Cr(Ⅲ)treatment.The strain BNC-Q was identified as Bacillus aryabhattai based on 16S rDNA PCR amplication analysis.The reproduction of BNC-Q being promoted by no more than 2 mmol/L Cr(Ⅲ)and still being available at 5 mmol/L Cr(Ⅲ)concentration showed that BNC-Q had a high tolerance to Cr(Ⅲ)based on the Cr(Ⅲ)treatment culture test.Protein expression analysis showed that a 40 ku protein was induced from BNC-Q with 2 mmol/L Cr(Ⅲ)treatment.The results of antioxidant analysis showed that BNC-Q had no effect on DPPH radical scavenging, while the scavenging rate of superoxide anion radical(O₂^-·)and hydroxyl radical(·OH)was increased from 63.7%, 63.5% to 91.1%, 85.2% respectively with 2 mmol/L Cr(Ⅲ)treatment.In summary, BNC-Q with strong tolerance to Cr(Ⅲ)was identified as Bacillus aryabhattai, and could be induced to express a 40 ku protein by Cr(Ⅲ), while the ability of scavenging superoxide anion radical and hydroxyl radical was significantly improved by Cr(Ⅲ).The research results can provide a basis for the bioremediation of Cr.

Key words: Brassica napus L. Bacillus aryabhattai, Chromium(Ⅲ)-resistance, SDS-PAGE, Antioxidation

中图分类号: 

• S432.4