Abalone gut microbiota

Holobionts have a digestive microbiota with catabolic abilities allowing the degradation of complex dietary compounds for the host. In terrestrial herbivores, the digestive microbiota is known to degrade complex polysaccharides from land plants while in marine herbivores, the digestive microbiota is poorly characterized. Most of the latter are generalists and consume red, green, and brown macroalgae, three distinct lineages characterized by a specific composition in complex polysaccharides, which represent half of their biomass. Subsequently, each macroalga features a specific epiphytic microbiota, and the digestive microbiota of marine herbivores is expected to vary with a monospecific algal diet. We investigated the effect of four monospecific diets (Palmaria palmata, Ulva lactuca, Saccharina latissima, Laminaria digitata) on the composition and specificity of the digestive microbiota of a generalist marine herbivore, the abalone, farmed in a temperate coastal area over a year. The microbiota from the abalone digestive gland was sampled every 2 months and explored using metabarcoding. Full article here: https://doi.org/10.1186/s40168-018-0430-7

共生功能体（Holobionts）的消化微生物群具备分解代谢能力，可帮助宿主降解复杂的膳食化合物。对于陆地草食动物而言，其消化微生物群可降解陆生植物来源的复杂多糖，这一点已得到广泛证实；但海洋草食动物的消化微生物群则研究程度较低。多数海洋草食动物为广食性物种，以红藻、绿藻和褐藻为食；这三类大型藻类分属不同演化支系，其复杂多糖组成具有特异性，而多糖占其生物量的一半。进一步而言，每一种大型藻类均拥有专属的附生微生物群，因此海洋草食动物的消化微生物群预计会随单一藻类日粮发生改变。
本研究以温带沿海地区养殖、饲养周期达一年的广食性海洋草食动物鲍鱼为对象，探究了4种单一藻类日粮（掌状红皮藻Palmaria palmata、石莼Ulva lactuca、宽叶海带Saccharina latissima、掌状海带Laminaria digitata）对其消化微生物群组成与特异性的影响。研究人员每2个月采集一次鲍鱼消化腺的微生物群样本，并采用元条形码测序（metabarcoding）技术对其进行分析。
完整论文详见：https://doi.org/10.1186/s40168-018-0430-7