Digestive microbiota provide a wide range of beneficial effects on host physiology and are therefore likely to play a key role in marine intertidal bivalve ability to acclimatize to the intertidal zone. This study investigated the effect of intertidal levels on the digestive bacterial microbiota of oysters (Crassostrea gigas) and clams (Ruditapes philippinarum), two bivalves with different ecological niches. Based on 16S rRNA region sequencing, digestive glands, seawater and sediments harbored specific bacterial communities, dominated by operational taxonomic units assigned to the Mycoplasmatales,Desulfobacterales and Rhodobacterales orders, respectively. Field implantation modified digestive bacterial microbiota of both bivalve species according to their intertidal position. Rhodospirillales and Legionellales abundances increased in oysters and clams from the low intertidal level, respectively. After a 14-day depuration process, these effects were still observed, especially for clams, while digestive bacterial microbiota of oysters were subjected to more short-term environmental changes. Nevertheless, 3.5 months stay on an intertidal zone was enough to leave an environmental footprint on the digestive bacterial microbiota, suggesting the existence of autochthonous bivalve bacteria. When comparing clams from the three intertidal levels, 20% of the bacterial assemblage was shared among the levels and it was dominated by an operational taxonomic unit affiliated to the Mycoplasmataceae and Spirochaetaceae families.

中文翻译：

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海洋潮间带塑造牡蛎和蛤类消化细菌微生物群。

消化微生物群对宿主生理学具有广泛的有益作用，因此可能在海洋潮间双壳类动物适应潮间带的能力中发挥关键作用。这项研究调查了潮间带水平对牡蛎（Crassostrea gigas）和蛤（Ruditapes philippinarum）（具有不同生态位的两个双壳类）的消化细菌微生物群的影响。基于16S rRNA区域测序，消化腺，海水和沉积物具有特定的细菌群落，主要由分配给支原体，脱硫细菌和红细菌的操作生物分类单位控制。订单。田间种植根据潮间带位置修改了两个双壳类的消化细菌菌群。红螺旋藻和军团菌潮间带水平较低时，牡蛎和蛤的丰度分别增加。经过14天的净化过程后，仍观察到了这些影响，特别是对蛤而言，而牡蛎的消化细菌微生物群则经历了更短期的环境变化。然而，在潮间带停留3.5个月就足以在消化细菌微生物群上留下环境足迹，这表明存在自生双壳类细菌。当比较三个潮间带的蛤时，在各个级别之间共有20％的细菌群落，并且由支原体科和螺旋藻科的一个操作分类单位控制。