抗砷性微生物及其抗砷分子机制研究进展.PDF

微生物学通报 AUG 20, 2009, 36(8): 1253~1259 Microbiology © 2009 by Institute of Microbiology, CAS tongbao@ 专论与综述 抗砷性微生物及其抗砷分子机制研究进展 蔡 林 王革娇* ( 430070) 摘 要: 砷 (Arsenic, As) 是一种剧毒类金属(Metalloid), 在自然环境中主要以三价亚砷酸盐 [Arsenite, AsO2−, As(III)]和五价砷酸盐[Arsenate, AsO43−, As(V)]的无机形式广泛存在。许多微生物 在含砷环境的长期适应过程中, 进化了多种不同的砷解毒抗性机制。目前研究发现主要存在 4 种 类型的砷抗性机理, 包括: As(III)氧化, 细胞质As(V)还原, 呼吸性 As(V)还原, As(III) 甲基化, 这些 机制赋予微生物砷抗性并在砷的转化和地球化学循环中起着极其重要的作用。本文主要介绍这几 种微生物砷抗性机制的机理及研究概况和潜在的砷污染生物修复功能。 关键词: 砷, 抗砷性微生物, 砷氧化, 砷还原, 砷甲基化, 砷污染, 生物修复 Advance on Studies of Arsenic-resistant Microorganisms and Molecular Mechanisms * CAI Lin WANG Ge-Jiao (State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei 430070, China) Abstract: Arsenic is known as a toxic metalloid, which mainly exists in inorganic forms such as arsenite and arsenate in the natural environment. A number of microorganisms have evolved different resistant mecha- nisms for arsenic detoxification to cope with the widespread distribution of the poisonous arsenic. Four dis- tinct microbial arsenic-resistant mechanisms have been described including As(III) oxidation, cytoplasmic As(V) reduction, respiratory As(V) reduction, and As(III) methylation. These mechanisms confer arsenic re- sistance in microorganisms that play important roles in the transformation and geological cycle of arsenic. This review mainly focuses on the researches on these molecular mechanisms and p