Reductive dehalogenation of 3,5-dibromo-4-hydroxybenzoate by an aerobic strain of Delftia sp EOB-17
Reductive dehalogenation of 3,5-dibromo-4-hydroxybenzoate by an aerobic strain of Delftia sp EOB-17
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需氧菌株 Delftia sp EOB-17 对 3,5-二溴-4-羟基苯甲酸酯的还原脱卤
DOI：
10.1007/s10529-015-1932-z
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发表时间：
2015-12-01
影响因子：
2.7
通讯作者：
Jiang, Jiandong
中科院分区：
文献类型：
--
作者：
Chen, Kai;Jian, Shanshan;Jiang, Jiandong
目的确定Delftiasp. EOB-17好氧菌的还原脱卤能力，为还原脱卤在好氧菌中广泛存在的假说提供更多的证据。在琥珀酸钠存在下，在有氧条件下，在28小时内完全降解0.2 mM DBHB并释放两当量的溴化物。LC-MS分析表明，DBHB通过连续还原脱卤经由3-溴-4-羟基苯甲酸酯转化为4-羟基苯甲酸酯。通过基因组测序，在EOB-17菌株中发现了高度保守的DBHB降解基因，包括还原性脱卤酶基因（bhbA 3）和胞质外结合受体基因（bhbB 3）。DBHB还原脱卤活性的最适温度为30 ℃，最适pH值为8，0.1mM的Cd 2+、Cu 2+、Hg 2+、Zn 2+对DBHB还原脱卤活性有强烈的抑制作用。为支持还原脱卤广泛发生在好氧细菌中的假设提供了另一个证据。
Objectives To confirm the reductive dehalogenation ability of the aerobic strain of Delftia sp. EOB-17, finding more evidences to support the hypothesis that reductive dehalogenation may occur extensively in aerobic bacteria.Results Delftia sp. EOB-17, isolated from terrestrial soil contaminated with halogenated aromatic compounds, completely degraded 0.2 mM DBHB in 28 h and released two equivalents of bromides under aerobic conditions in the presence of sodium succinate. LC-MS analysis revealed that DBHB was transformed to 4-hydroxybenzoate via 3-bromo-4-hydroxybenzoate by successive reductive dehalogenation. Highly conserved DBHB-degrading genes, including reductive dehalogenase gene (bhbA3) and the extra-cytoplasmic binding receptor gene (bhbB3), were also found in strain EOB-17 by genome sequencing. The optimal temperature and pH for DBHB reductive dehalogenation activity are 30 degrees C and 8, respectively, and 0.1 mM Cd2+, Cu2+, Hg2+ and Zn2+ strongly inhibited dehalogenation activity.Conclusions The aerobic strain of Delftia sp. EOB-17 was confirmed to reductively dehalogenate DBHB under aerobic conditions, providing another evidence to support the hypothesis that reductive dehalogenation occurs extensively in aerobic bacteria.