TY - JOUR T1 - External pH modulation during the growth of Vibrio tapetis, the aetiological agent of brown ring disease A1 - Rahmani,Alexandra A1 - Mathien,Clémentine A1 - Bidault,Adeline A1 - Le Goïc,Nelly A1 - Paillard,Christine A1 - Pichereau,Vianney AD - Univ Brest ,CNRS IRD, Ifremer UMR 6539 LEMAR F‐29280 Plouzané, France AD - Univ Brest ,CNRS IRD, Ifremer UMR 6539 LEMAR F‐29280 Plouzané, France UR - https://doi.org/10.1111/jam.14699 DO - 10.1111/jam.14699 KW - BRD KW - modulation effect KW - neutralizing activity KW - pH KW - pH modifications KW - Ruditapes philippinarum KW - Vibrio tapetis N2 - Aims Brown Ring Disease (BRD) is an infection of the Manila clam Ruditapes philippinarum due to the pathogen Vibrio tapetis. During BRD, clams are facing immunodepression and shell biomineralization alteration. In this paper, we studied the role of pH on the growth of the pathogen and formulated hypothesis on the establishment of BRD by V. tapetis. Methods and Results In this study, we monitored the evolution of pH during the growth of V. tapetis in a range of pH and temperatures. We also measured the pH of Manila clam hemolymph and extrapallial fluids during infection by V. tapetis. We highlighted that V. tapetis modulates the external pH during its growth, to a value of 7.70. During the development of BRD, V. tapetis also influences extrapallial fluids and hemolymph pH in vitro in the first hours of exposure and in vivo after 3 days of infection. Conclusions Our experiments have shown a close interaction between V. tapetis CECT4600, a pathogen of Manila clam that induces BRD, and the pH of different compartments of the animals during infection. These results indicate that that the bacterium, through a direct mechanism or as a consequence of physiological changes encountered in the animal during infection, is able to interfere with the pH of Manila clam fluids. This pH modification might promote the infection process or at least create an imbalance within the animal, that would favor its persistence. This last hypothesis should be tested in future experiment. Significance and Impact of Study This study is the first observation of pH modifications in the context of BRD and might orient future research on the fine mechanisms of pH modulation associated to BRD. Y1 - 2020/07 PB - Wiley JF - Journal Of Applied Microbiology SN - 1364-5072 VL - 129 IS - 1 SP - 3 EP - 16 ID - 74142 ER -