Shi Guang-Yu, Yin Hua, Ye Jin-Shao, Peng Hui, Zhang Na, He Bao-Yan
Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
Huan Jing Ke Xue. 2013 Apr;34(4):1517-23.
The degradation characteristics of decabromodiphenyl ether (BDE-209) by crude enzyme from Pseudomonas aeruginosa were investigated. The results revealed that the degradation efficiency of the intracellular enzyme excreted from this bacterial strain reached 69.22% after incubation with 1 mg x L(-1) BDE-209 for 12 h. Temperature, pH, enzyme concentration and BDE-209 concentration all influenced the ability of crude enzyme to degrade BDE-209. When the BDE-209 concentration was 1 mg x L(-1), the optimal condition for enzymatic degradation was temperature 30 degrees C and pH 7.5, and the degradation rate increased with increasing enzyme concentration. The degradation process of BDE-209 by intracellular enzyme of the strain conformed to the first-order kinetic model. The highest reaction rate was achieved when the initial concentration of BDE-209 was 1 mg x L(-1) and the half-life of this substrate was 6.9 h. In addition, the biodegradation of BDE-209 can be well described by enzymatic reaction of high concentration substrate inhibition, with a maximum substrate utilization rate of 0.133 mg x (L x h)(-1), a Michaelis-Menten constant of 0.642 mg x L(-1), and an inhibitory constant of 1.558 mg x L(-1), respectively.
研究了铜绿假单胞菌粗酶对十溴二苯醚（BDE - 209）的降解特性。结果表明，该菌株分泌的胞内酶与1 mg·L⁻¹ BDE - 209孵育12 h后，降解效率达到69.22%。温度、pH值、酶浓度和BDE - 209浓度均影响粗酶降解BDE - 209的能力。当BDE - 209浓度为1 mg·L⁻¹时，酶促降解的最佳条件为温度30℃、pH值7.5，且降解率随酶浓度增加而升高。该菌株胞内酶对BDE - 209的降解过程符合一级动力学模型。当BDE - 209初始浓度为1 mg·L⁻¹时，反应速率最高，该底物的半衰期为6.9 h。此外，BDE - 209的生物降解可用高浓度底物抑制的酶促反应很好地描述，最大底物利用率为0.133 mg·(L·h)⁻¹，米氏常数为0.642 mg·L⁻¹，抑制常数为1.558 mg·L⁻¹。
