Degradation of ambient carbonyl sulfide by Mycobacterium spp. in soil
Degradation of ambient carbonyl sulfide by Mycobacterium spp. in soil
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DOI：
10.1099/mic.0.2007/011213-0
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发表时间：
2008-01-01
期刊：
影响因子：
2.8
通讯作者：
Katayama, Yoko
中科院分区：
文献类型：
--
作者：
Kato, Hiromi;Saito, Masahiko;Katayama, Yoko
在不添加COS的情况下，从土壤中分离出7株菌株，证实其降解羰基硫化物（COS）的能力。比较16S rRNA基因序列分析表明，分离株分别属于分枝杆菌属、威廉属和铜属。例如，在PYG琼脂培养基上生长的分枝杆菌（Mycobacterium sp.）菌株THI401能够在1小时内降解初始水平为百万分之30的COS，而在30小时内通过非生物转化降低了60%的初始COS。考虑到土壤和大气之间的自然COS通量，这些细菌在环境水平为500万亿分之几体积（p.p.t.v）时被证实降解。高压灭菌土壤导致少量COS排放，而分枝杆菌降解COS的速度快于其从土壤中排放的速度，并将COS的混合比降低到低于环境水平：THI401在30 h内将COS从初始的530 p.p.t.v.降解到330 p.p.t.v.。这些结果为土壤中微生物作为大气COS汇的活性提供了实验证据。
The ability to degrade carbonyl sulfide (COS) was confirmed in seven bacterial strains that were isolated from soil, without the addition of COS. Comparative 16S rRNA gene sequence analysis indicated that these isolates belonged to the genera Mycobacterium, Williamsia and Cupriavidus. For example, Mycobacterium sp. strain THI401, grown on PYG agar medium, was able to degrade an initial level of 30 parts per million by volume COS within 1 h, while 60% of the initial COS was decreased by abiotic conversion in 30 h. Considering natural COS flux between soil and the atmosphere, COS degradation by these bacteria was confirmed at an ambient level of 500 parts per trillion by volume (p.p.t.v.), using sterilized soil to cultivate the bacterium. Autoclave sterilization of soil resulted in a small amount of COS emission, while Mycobacterium spp. degraded COS at a faster rate than it was emitted from the soil, and reduced the COS mixing ratio to a level that was lower than the ambient level: THI401 degraded COS from an initial level of 530 p.p.t.v. to a level of 330 p.p.t.v. in 30 h. These results provide experimental evidence of microbial activity in soil as a sink for atmospheric COS.