久效磷降解菌的分离及其酶促降解特性研究 |
摘要点击 2210 全文点击 2098 投稿时间:2006-05-09 修订日期:2006-06-30 |
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 久效磷 生物降解 Paracoccus sp. 酶促降解 |
英文关键词 monocrotophos biodegradation Paracoccus sp. enzymatic degradation |
|
中文摘要 |
从某农药厂废水处理池的污泥中分离到1株久效磷高效降解菌株M-1,经过对其形态特征、生理生化、以及16S rDNA序列分析,该菌株初步鉴定为Paracoccus sp..M-1能以久效磷作为唯一碳源生长,24 h对100 mg·L-1久效磷的降解效率为92.47%.久效磷降解酶定域表达试验表明该酶为胞内酶,组成表达.久效磷酶促降解的最适反应pH为8.0,最适反应温度为25 ℃;其米氏常数(Km)为0.29 μmol·mL-1,最大降解速率(Vmax)为682.12 μmol·(min·mg)-1.久效磷降解酶热稳定性差,碱性条件下能够保持较高降解活性. |
英文摘要 |
A monocrotophos [dimethyl (E)-1-2-methylcarbamoylvinylphosphate or MCP] -degrading strain named as M-1 was isolated from sludge collected from the wastewater treatment pool of a pesticide factory and identified as Paracoccus sp. according to its morphology and biochemical properties and 16S rDNA sequence analysis. Using MCP as a sole carbon source, M-1 was able to degrade MCP(100 mg·L-1) by 92.47% in 24 h. The key enzyme(s) involved in the initial biodegradation of monocrotophos in M-1 was shown to be constitutively expressed cytosolic proteins and showed the greatest activity at pH 8.0 and 25 ℃, with its Michaelis-Mentn's constant (Km) and maximum degradation rate (Vmax) of 0.29 μmol·mL-1 and 682.12 μmol·(min·mg)-1 respectively. This degrading enzyme(s) was sensitive to high temperature, but kept high activity under alkaline conditions. |