Biodegradation of Pentachloronitrobenzene by I.abrys portucalensis pcnb-21 Isolated from Polluted Soil

• Published in: Pedosphere 2011, Vol.21 (1), p.31-36
• Main Author: LI Rong ZHENG Jin-Wei NI Bin CHEN Kai YANG Xiu-Juan LI Shun-Peng JIANG Jian-Dong
• Format: Article
• Language: English
• Subjects: 五氯硝基苯; 初始pH值; 基因序列分析; 污染土壤; 生物降解; 生理生化基础; 绿色荧光蛋白
• ISSN: 1002-0160; 2210-5107

A bacterial strain, pcnb-21, capable of degrading pentaehloronitrobenzene （PCNB） under aerobic and anoxic conditions, was isolated from a long-term PCNB-polluted soil by an enrichment culture technique and identified as Labrys portucalensis based upon its morphological, physiological and biochemical properties, as well as 16S rRNA gene sequence analysis. Effects of different factors, such as temperature and pH, on PCNB biodegradation were studied. Strain pcnb-21 efficiently degraded PCNB at temperatures from 20 to 30 ℃ and initial pH values from 4 to 7, which might be the first time that a Labrys strain was found capable of eflClciently degrading PC1NB. The degradation of PCNB was affected by oxygen, and the degradation decreased with increasing aeration. Exogenous electron donors such as glucose, lactic acid and succinic acid promoted the biodegradation of PCNB, while electron acceptors such as sodium nitrite, sodium sulfate, sodium nitrate and sodium sulfate inhibited PCNB biodegradation. The degradation of PCNB in sterile and non-sterile soils by a green fluorescent protein （GFP）-labeled strain, pcnb-21-gfp, was also studied. Cells of pcnb-21-gfp efficiently degraded 100 mg kg-1 PCNB in sterile and non-sterile soils and could not be detected after 42 days. Strain pcnb-21 might be useful in bioremediating PCNB-polluted soils and environment.