A fate for organic acids, formaldehyde and methanol in cloud water: their biotransformation by micro-organisms
A fate for organic acids, formaldehyde and methanol in cloud water: their biotransformation by micro-organisms
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DOI：
10.5194/acp-7-4159-2007
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发表时间：
2007-01-01
影响因子：
6.3
通讯作者：
Delort, A.-M.
中科院分区：
文献类型：
--
作者：
Amato, P.;Demeer, F.;Delort, A.-M.
研究了云水中微生物与化学成分的相互作用。首先，我们观察到大量的云水溶液提供了一个细菌可以显著发展的实质环境。然后，从7个不同的云水样品中提取了60株微生物菌株，并隶属于不同的分类群，研究了它们降解大气中一些主要羧基化合物的能力：甲酸盐、乙酸盐、乳酸盐、琥珀酸盐、甲醛和甲醇。生物降解试验表明，所有这些化合物在作为单一碳质底物使用时都可以转化，其活性取决于菌株和化合物。对甲醛、甲酸酯和醋酸酯的生物降解能力最高，这也是通常在云水中测量到的浓度较高的化合物。因此，通过H-1核磁共振分析可以确定，例如，丙酮酸盐或富马酸盐等化合物可以在与乳酸盐或琥珀酸盐转化有关的介质中产生和释放。此外，对C-13标记甲醛的利用表明，它可以通过许多代谢途径转化，类似于光化学诱导的代谢途径，并导致甲酸盐和/或甲醇的产生。这些结果表明，云水中的微生物可以对大气中存在的化合物有不同的行为：它们可以代表有机碳的汇或源，并且可能必须被视为云化学的参与者。
The interactions between microbial and chemical contents of cloud water were investigated. First, we observe that the bulk cloud water solution provides a substantial environment where bacteria can develop significantly. Then, a total number of 60 microbial strains originating from seven distinct samples of cloud water and affiliated to various taxonomic groups were examined for their ability to degrade some of the main atmospheric carboxylic compounds: formate, acetate, lactate, succinate, as well as formaldehyde and methanol. Biodegradation tests show that all these compounds can be transformed when used as single carbonaceous substrates, with activities depending on both the strain and the compound. The highest capacities of biodegradation are observed towards formaldehyde, formate and acetate, which are also the more concentrated compounds typically measured in cloud water. Hence, analyses by H-1 NMR permitted to establish for instance that compounds like pyruvate or fumarate can be produced and released in the media in relation to the transformation of lactate or succinate. In addition, utilization of C-13 labelled formaldehyde showed that it can be transformed through many metabolic pathways, similar to those induced by photochemistry and leading to the production of formate and/or methanol. These results suggest that microorganisms of cloud water can have various behaviours towards the chemical compounds present in the atmosphere: they can represent either a sink or source for organic carbon, and may have to be considered as actors of cloud chemistry.