sequences of bacteria
DNA was extracted from the gut samples of Pseudogastromyzon fasciatus using a commercial kit, with quality verified by 1% agarose gel electrophoresis and concentration measured using a NanoDrop2000. The 16S rRNA gene (V3-V4 region) was amplified using universal primers (338F and 806R) in a 20 L PCR reaction, followed by purification and quantification. Libraries were constructed using the TruSeq DNA Sample Prep Kit and sequenced on an Illumina MiSeq PE300 platform.