MICROBIOME DYNAMICS OF MUD CRAB Scylla paramamosain FOLLOWING MOLTING

Xinxu Zhang*, Shengkang Li
 
 Marine Biology Institute, Shantou University
 Daxue Road 243, Shantou, P.R.China, 515063
 newsunzhang@stu.edu.cn

Symbiotic microorganisms living in the host or on its surface play a key role in the host's digestion and immunity, which is a research hotspot in recent years. The mud crab Scylla paramamosain is a commercially important aquaculture species in the southeast coast of China. Our previous results revealed the abundance and diversity of microbial communities in different mud crab tissues, including intestine, gill, hemolymph and subcuticular epidermis. Molting is an important process for the arthropods and some reptiles throughout its lifetime, which is related to its growth, reproduction and appendage regeneration. During a molting, the animal tries to escape from the confines of old exoskeletons and tissues (such as gill and intestine) when the connectives between the living tissues and the extracellular cuticles were loosen. However, little is known about the dynamic change of the microbiome in Scylla paramamosain following molting. In the present study, we aim to investigate whether molting affected the host microbiome, and to test the hypothesis that a recolonization event occurs in the host microbiome of the crab following molting. To this end, we have determined the microbial abundance and bacterial community compositions in different molting stages of the crabs, by using fluorescence microscopy and barcoded high-throughput sequencing of the V3-V4 region of the 16S rRNA genes. Distinct patterns of microbial communities were observed before and after molting, showing a dynamic change of the host microbiome following molting. Meanwhile, this study gives clues to develop microbial immunoenhancer, and to select appropriate administration routes for disease control.