Department of Ecology and Evolution, University of Chicago , Chicago, IL , USA.
Department of Ecology and Evolution, University of Chicago , Chicago, IL , USA ; Institute of Genomic and Systems Biology, Argonne National Laboratory , Lemont, IL , USA.
PeerJ. 2014 Oct 16;2:e631. doi: 10.7717/peerj.631. eCollection 2014.
Rocky shore microbial diversity presents an excellent system to test for microbial habitat specificity or generality, enabling us to decipher how common macrobiota shape microbial community structure. At two coastal locations in the northeast Pacific Ocean, we show that microbial composition was significantly different between inert surfaces, the biogenic surfaces that included rocky shore animals and an alga, and the water column plankton. While all sampled entities had a core of common OTUs, rare OTUs drove differences among biotic and abiotic substrates. For the mussel Mytilus californianus, the shell surface harbored greater alpha diversity compared to internal tissues of the gill and siphon. Strikingly, a 7-year experimental removal of this mussel from tidepools did not significantly alter the microbial community structure of microbes associated with inert surfaces when compared with unmanipulated tidepools. However, bacterial taxa associated with nitrate reduction had greater relative abundance with mussels present, suggesting an impact of increased animal-derived nitrogen on a subset of microbial metabolism. Because the presence of mussels did not affect the structure and diversity of the microbial community on adjacent inert substrates, microbes in this rocky shore environment may be predominantly affected through direct physical association with macrobiota.
岩岸微生物多样性提供了一个极好的系统来检验微生物生境的特异性或普遍性，使我们能够揭示常见的大型生物如何塑造微生物群落结构。在北太平洋东北部的两个沿海地区，我们表明，微生物组成在惰性表面、包括岩岸动物和藻类的生物表面以及水柱浮游生物之间存在显著差异。虽然所有采样实体都有一个共同的 OTU 核心，但稀有 OTU 导致了生物和非生物基质之间的差异。对于贻贝 Mytilus californianus，壳表面的 alpha 多样性比鳃和虹吸管内部组织更高。引人注目的是，与未受干扰的潮池相比，将这种贻贝从潮池中去除 7 年的实验并没有显著改变与惰性表面相关的微生物群落结构。然而，与硝酸盐还原相关的细菌类群在贻贝存在时具有更高的相对丰度，这表明动物来源的氮增加对微生物代谢的一部分产生了影响。由于贻贝的存在并没有影响相邻惰性基质上微生物群落的结构和多样性，因此在这种岩岸环境中的微生物可能主要通过与大型生物的直接物理联系而受到影响。
