Department for Bioorganic Analytics, Friedrich Schiller University Jena, 07743 Jena, Germany.
Department of Biology, Division of Genetics and Physiology, University of Turku, FI-20014 Turku, Finland.
Mar Drugs. 2012 Apr;10(4):775-792. doi: 10.3390/md10040775. Epub 2012 Mar 28.
Several marine and freshwater diatoms produce polyunsaturated aldehydes (PUA) in wound-activated processes. These metabolites are also released by intact diatom cells during algal blooms. Due to their activity in laboratory experiments, PUA are considered as potential mediators of diatom-bacteria interactions. Here, we tested the hypothesis that PUA mediate such processes in a close-to-field mesocosm experiment. Natural plankton communities enriched with Skeletonema marinoi strains that differ in their PUA production, a plankton control, and a plankton control supplemented with PUA at natural and elevated concentrations were observed. We monitored bacterial and viral abundance as well as bacterial community composition and did not observe any influence of PUA on these parameters even at elevated concentrations. We rather detected an alternation of the bacterial diversity over time and differences between the two S. marinoi strains, indicating unique dynamic bacterial communities in these algal blooms. These results suggest that factors other than PUA are of significance for interactions between diatoms and bacteria.
几种海洋和淡水硅藻在伤口激活过程中产生多不饱和醛 (PUA)。这些代谢物也会在藻类大量繁殖期间由完整的硅藻细胞释放。由于它们在实验室实验中的活性，PUA 被认为是硅藻-细菌相互作用的潜在介质。在这里，我们在接近野外的中观实验中测试了 PUA 介导这些过程的假设。观察了用产生不同 PUA 的 S. marinoi 菌株富集的天然浮游生物群落、浮游生物对照以及补充了天然和升高浓度 PUA 的浮游生物对照。我们监测了细菌和病毒丰度以及细菌群落组成，即使在升高的浓度下，也没有观察到 PUA 对这些参数的任何影响。相反，我们检测到细菌多样性随时间的交替变化以及两种 S. marinoi 菌株之间的差异，表明这些藻类大量繁殖中存在独特的动态细菌群落。这些结果表明，对于硅藻和细菌之间的相互作用，除了 PUA 之外，还有其他因素具有重要意义。
