| 克雷伯氏菌对三苯基锡的酶促降解特性 |
| 摘要点击 2430 全文点击 2422 投稿时间：2009-03-27 修订日期：2009-05-31 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 肺炎克雷伯氏菌 三苯基锡 有机锡 降解酶 生物降解 |
| 英文关键词 Klebsiella pneumoniae triphenyltin organotin degrading-enzyme biodegradation |
|
| 中文摘要 |
| 研究了肺炎克雷伯氏菌对三苯基锡（TPhT）的酶促降解性能，并对酶促反应影响因素的作用机制进行了探讨，以期为阐明有机锡的微生物降解机制提供实验依据.研究证明，菌体、分泌物和胞内降解酶均具有降解TPhT的能力，在30℃转速为130 r·min-1的摇床中避光处理2 h后，对3 mg·L-1TPhT的降解率分别为10.9%、5.3%和47.9%. 影响因素实验表明，降解介质、pH、温度、TPhT浓度和金属离子均会对TPhT的酶促降解效果产生影响，其中TPhT酶促反应的 |
| 英文摘要 |
| The objective of this study is to illuminate the mechanism of biodegradation of triphenyltin (TPhT). The removal of TPhT by Klebsiella pneumoniae was,therefore,investigated through characteristics studies. The influences of the various parameters were also discussed. The results demonstrated that the cell,extracellular secretion and intracellular enzyme were the effective biomasses for the biodegradation of TPhT. At initial concentration of 3 mg·L-1,10.9%,5.3% and 47.9% of TPhT could be degraded by these biomasses respectively at 30℃ within 2 hours under an rotary shaker at 120 r·min-1. The experimental results also showed that the enzyme activity could be affected by the buffers,pH,temperature,metals and the concentration of TPhT. The degradation efficiency would reach the highest point at pH 8,and at the optimal temperature of 50℃. Metals including Mg2+,Mn2+,Fe2+ and Fe3+ improved the enzyme activity at certain concentrations. In the presence of 15 mg·L-1 of Mg2+,the removal percentage of TPhT was up to 73.8%. It suggested that the metals activated the enzyme and interacted with the TPhT enabling its removal during the biodegradation process. Linear plots of removal ratios versus concentrations of TPhT meant that the biodegradation fitted the Michaelis-Menten model. The Vmax and Kmm of this biodegradation were 0.15 mg·(L·min)-1 and 47.1 mg·L-1,respectively. |
|
|
|
