Institut de Chimie de Clermont-Ferrand, Université Clermont Auvergne, Université Blaise Pascal , BP 10448, F-63000 Clermont-Ferrand, France.
CNRS, UMR 6296, Institut de Chimie de Clermont-Ferrand (ICCF) , F-63171 Aubiere, France.
Environ Sci Technol. 2016 Sep 6;50(17):9315-23. doi: 10.1021/acs.est.6b02335. Epub 2016 Aug 18.
A total of 450 bacteria and yeast strains isolated from cloud waters sampled at the puy de Dôme station in France (1465 m) were screened for their ability to produce siderophores. To achieve this, a high-throughput method in 96-well plates was adapted from the CAS (chrome azurol S) method. Notably, 42% of the isolates were siderophore producers. This production was examined according to the phyla of the tested strains and the type of chelating functional groups (i.e., hydroxamate, catechol, and mixed type). The most active bacteria in the clouds belong to the γ-Proteobacteria class, among which the Pseudomonas genus is the most frequently encountered. γ-Proteobacteria are produced in the majority of mixed function siderophores, such as pyoverdines, which bear a photoactive group. Finally, siderophore production was shown to vary with the origin of the air masses. The organic speciation of iron remains largely unknown in warm clouds. Our results suggest that siderophores could partly chelate Fe(III) in cloud waters and thus potentially impact the chemistry of the atmospheric aqueous phase.
从法国多姆山站采集的云水中共分离出 450 株细菌和酵母菌株，对其产生铁载体的能力进行了筛选。为了实现这一目标，我们从 CAS（铬天青 S）方法中改编了一种高通量 96 孔板方法。值得注意的是，42%的分离株是铁载体产生菌。根据测试菌株的门和螯合功能基团的类型（即羟肟酸盐、儿茶酚和混合类型）来检查这种产生情况。云层中最活跃的细菌属于γ-变形菌纲，其中假单胞菌属最为常见。γ-变形菌纲产生大多数混合功能铁载体，例如具有光活性基团的绿脓菌素。最后，铁载体的产生与气团的来源有关。在暖云中，铁的有机形态仍然很大程度上未知。我们的结果表明，铁载体可能部分螯合云水中的 Fe(III)，从而可能影响大气水相的化学性质。
