微生物代谢环境难降解性有机物的酶学研究进展

Progress in study on microbial enzymes for the metabolism of environmental refractory organic compounds

摘要:

随着人类社会的快速发展, 工业化水平不断提高, 产生大量的污染物并排放到环境中, 给人类的生活和身体健康造成了严重的影响。这些污染物中包含种类繁多的难降解有机物, 如多芳香烃(PAHs)、环硝胺类物质(RDX、HMX和CL-20)、多氯联苯(PCBs)及烷烃类化合物等, 对自然界的污染危害大。微生物可以消除它们对污染的影响, 研究结果表明微生物的代谢或共代谢活动是降解这些物质的有效途径, 降解起始阶段需要一些关键酶的参与活动, 以氧化还原酶为主。这些氧化还原酶一般与细胞膜上其他的活性组分在一起, 形成一个氧化还原系统氧化底物。被氧化的中间物质再通过一系列酶催化继续氧化成三羧酸中间代谢产物被微生物所利用。以下综述了与这些物质降解相关的代谢途径和关键的酶, 展望今后在开展这类研究工作时要加强降解微生物的筛选和相关酶学的研究, 进一步研究这些污染物的代谢或共代谢途径和机理, 为工程化治理环境污染提供依据。

Abstract:

With the rapid development of socialization and industrialization, more and more pollutes were produced and discharged into natural environment. It is harmful to human health and life. These pollutes included refractory degradation organic compounds like PAHs, RDX, HMX, CL-20, PCBs and alkanes and their relative substances. Various compounds exist in nature with long life span. They are the most hazardous than other organics. The impact of pollutes can be treated by microorganisms. Result showed that it is an effective way for bioremediation of these pollutes with microbial metabolism or cometabolism. A few key enzymes, mainly oxidative and reductive enzymes, connected with the first step of initial degradation. Normally, enzymes grouped with other active fraction on the cell membrane are composed of one oxidative and reductive system for substrates oxidation. The metabolic intermediates can be used with TCA by microorganisms. The pathways of metabolism and the key enzymes were summarized. The further research topics should be focused on microorganism screen and its relative enzyme, pathway and mechanism of metabolism or cometabolism for such compounds degradation, and the result was hoped for the environmental protection.