Cupriavidus in the intestinal microbiota of Tibet endemic fish Glyptosternum maculatum can help it adapt to habitat of the Qinghai Tibet Plateau

BACKGROUND: Gut microbes play an important role in the growth and development of fish. The Tibetan Plateau fish Glyptosternum maculatum is a unique species of sisorid catfish living in the river up to 4200 m altitude. RESULTS: To understand the mechanisms underlying the ability of G. maculatum to adapt to the high-altitude habitat, the intestinal microbiota of G. maculatum was studied. We used high-throughput sequencing of the 16S ribosomal RNA gene of intestinal microorganisms of wild and cultured G. maculatum to explore the characteristics of intestinal microorganisms and compared the gut microbial community of wild and cultured G. maculatum. The results showed that the α-diversity and richness of the intestinal microbiome were higher in wild G. maculatum than in cultured fish. The most abundant phylum in both G. maculatum were Fusobacteria, Proteobacteria, Firmicutes, and Bacteroidetes; Cetobacterium and Cupriavidus are the most dominant genus. The membership and structure of intestinal bacterial communities in wild G. maculatum are similar to the cultured fish, suggesting that a core microbiota is present in both G. maculatum intestinal bacterial communities. Metastats analysis showed that six genera were differentially represented between the wild and cultured G. maculatum. CONCLUSIONS: The most interesting characteristic of the intestinal microbial communities of G. maculatum is that there were large numbers of Cupriavidus, which may play an important role in the adaptation of G. maculatum to the water of the Yarlung Zangbo River with a high Cu content. This result, in turn, can guide us on breeding G. maculatum.