Nielsen Shaun J, Harder Tilmann, Steinberg Peter D
School of Biological, Earth and Environmental Sciences and Centre for Marine Bio-Innovation, The University of New South Wales, Sydney, 2052 NSW, Australia.
School of Biological, Earth and Environmental Sciences and Centre for Marine Bio-Innovation, The University of New South Wales, Sydney, 2052 NSW, Australia
FEMS Microbiol Ecol. 2015 Jan;91(1):1-9. doi: 10.1093/femsec/fiu011. Epub 2014 Dec 5.
Most marine invertebrates have dispersive larvae and relatively immobile adults. These developmental stages are linked by a settlement event, which is often mediated by specific cues in bacterial biofilms. While larvae distinguish between biofilms from different environments, it remains unknown if they receive information from all, only a few or even just a single bacterial species in natural biofilms. Here we asked how specific is larval settlement to the bacterial community structure and/or taxonomically distinguishable groups of bacteria in epiphytic marine biofilms? We used novel multivariate statistical approaches to investigate if larval settlement of two sea urchins correlated with the microbial community composition. Larval settlement of Heliocidaris erythrogramma revealed a strong correlation with the community composition, highlighted by canonical analysis of principle components, a constrained ordination technique. Using this technique, the importance of operational taxonomic units (OTUs) within communities relative to larval settlement was investigated. Larval settlement not only correlated, both positively and negatively, with the epiphytic bacterial community composition but also with the relative abundance of few OTUs within these communities. In contrast, no such correlation was observed for the other urchin, Holopneustes purpurascens, whose larvae likely respond to bacterial biofilms in a more general way and specifically respond to a defined settlement cue of algal origin.
大多数海洋无脊椎动物具有可扩散的幼虫和相对不活动的成体。这些发育阶段通过附着事件相联系，附着事件通常由细菌生物膜中的特定线索介导。虽然幼虫能够区分来自不同环境的生物膜，但它们是否从自然生物膜中的所有细菌、仅少数细菌甚至只是单一细菌物种接收信息仍不清楚。在这里，我们探讨了海洋附生生物膜中幼虫附着对细菌群落结构和/或分类学上可区分的细菌群体的特异性如何？我们使用新颖的多元统计方法来研究两种海胆的幼虫附着是否与微生物群落组成相关。红斑海胆（Heliocidaris erythrogramma）的幼虫附着与群落组成显示出强烈的相关性，主成分典型分析（一种受限排序技术）突出了这一点。使用该技术，研究了群落内操作分类单元（OTU）相对于幼虫附着的重要性。幼虫附着不仅与附生细菌群落组成呈正相关和负相关，还与这些群落中少数OTU的相对丰度相关。相比之下，对于另一种海胆——紫色全刺海胆（Holopneustes purpurascens），未观察到这种相关性，其幼虫可能以更普遍的方式对细菌生物膜做出反应，并对特定的藻类来源附着线索做出特异性反应。
