A variety of trace metals, including prominently iron (Fe) are necessary for marine microorganisms. Chemically defined medium recipes have been used for several decades to study phytoplankton, but similar methods have not been adopted as widely in studies of marine heterotrophic bacteria. Medium recipes for these organisms frequently include tryptone, casamino acids, as well as yeast and animal extracts. These components introduce unknown concentrations of trace elements and organic compounds, complicating metal speciation. Minimal medium recipes utilizing known carbon and nitrogen sources do exist but often have high background trace metal concentrations. Here we present H-Aquil, a version of the phytoplankton medium Aquil adapted for marine heterotrophic bacteria. This medium consists of artificial seawater supplemented with a carbon source, phosphate, amino acids, and vitamins. As in Aquil, trace metals are controlled using the synthetic chelator EDTA. We also address concerns of EDTA toxicity, showing that concentrations up to 100 µM EDTA do not lead to growth defects in the copiotrophic bacterium Vibrio harveyi or the oligotrophic bacterium Candidatus Pelagibacter ubique HTCC1062, a member of the SAR11 clade. H-Aquil is used successfully to culture species of Vibrio, Phaeobacter, and Silicibacter, as well as several environmental isolates. We report a substantial decrease in growth rate between cultures grown with or without added Fe, making the medium suitable for conducting Fe-limitation studies in a variety of marine heterotrophic bacteria.

中文翻译：

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H-Aquil：化学定义的细胞培养基，用于弧菌和其他海洋异养细菌中的痕量金属研究。

海洋微生物需要多种微量金属，包括显着的铁（Fe）。化学定义的培养基配方已用于研究浮游植物数十年，但在海洋异养细菌的研究中并未广泛采用类似的方法。这些生物的中等配方通常包括胰蛋白,、酪蛋白氨基酸以及酵母和动物提取物。这些成分会引入未知浓度的痕量元素和有机化合物，使金属形态复杂化。确实存在利用已知碳和氮源的最小培养基配方，但通常具有较高的本底痕量金属浓度。在这里，我们介绍H-Aquil，一种适用于海洋异养细菌的浮游植物培养基Aquil的版本。这种介质由人造海水和碳源组成，磷酸盐，氨基酸和维生素。与Aquil一样，使用合成螯合剂EDTA控制痕量金属。我们还解决了EDTA毒性问题，表明浓度高达100 µM的EDTA不会导致嗜营养弧菌哈维弧菌或寡营养细菌念珠菌HTCC1062（SAR11进化枝成员）的生长缺陷。H-Aquil已成功用于培养弧菌，Phaeobacter和Silicibacter菌种以及几种环境分离株。我们报道了在添加或不添加铁的情况下培养之间的生长速率显着降低，这使该培养基适合于在各种海洋异养细菌中进行铁限制研究。我们还解决了EDTA毒性问题，表明浓度高达100 µM的EDTA不会导致嗜营养弧菌哈维弧菌或寡营养细菌念珠菌HTCC1062（SAR11进化枝成员）的生长缺陷。H-Aquil已成功用于培养弧菌，Phaeobacter和Silicibacter菌种以及几种环境分离株。我们报道了在添加或不添加铁的情况下培养之间的生长速率显着降低，这使该培养基适合于在各种海洋异养细菌中进行铁限制研究。我们还解决了EDTA毒性问题，表明浓度高达100 µM的EDTA不会导致嗜营养弧菌哈维弧菌或寡营养细菌念珠菌HTCC1062（SAR11进化枝成员）的生长缺陷。H-Aquil已成功用于培养弧菌，Phaeobacter和Silicibacter菌种以及几种环境分离株。我们报道了在添加或不添加铁的情况下培养之间的生长速率显着降低，这使该培养基适合于在各种海洋异养细菌中进行铁限制研究。H-Aquil已成功用于培养弧菌，Phaeobacter和Silicibacter菌种以及几种环境分离株。我们报道了在添加或不添加铁的情况下培养之间的生长速率显着降低，这使该培养基适合于在各种海洋异养细菌中进行铁限制研究。H-Aquil已成功用于培养弧菌，Phaeobacter和Silicibacter菌种以及几种环境分离株。我们报道了在添加或不添加铁的情况下培养之间的生长速率显着降低，这使该培养基适合于在各种海洋异养细菌中进行铁限制研究。