大黄鱼养殖海域水体中细菌群落结构和抗生素抗性基因分布特征

Distributions of microbial communities and antibiotic resistance genes of water in the large yellow croaker(Larimichthys crocea)aquaculture

为探究大黄鱼福建养殖海域水体中微生物群落和抗生素抗性基因(ARG)的分布特征,本研究利用MiSeq和HiSeq高通量测序技术,基于细菌16S rRNA基因V3~V4可变区,对福建6个大黄鱼密集养殖区水体中的细菌群落结构和ARG赋存特征进行研究。Ribosomal Database Project(RDP)注释结果显示6个样品中丰度最高的门为Proteobacteria,占样品序列总数的59.62%~75.34%,不同位置大黄鱼养殖海域水体中的优势菌属存在显著差异(P<0.05)。通过与Comprehensive Antibiotic Resistance Database(CARD)数据库比对发现,水体中共检测出872个ARG,包括20种ARG基因类型;不同养殖区域的优势ARG类型基本一致,主要为四环素类、大环内酯类和氟喹诺酮类抗性基因;抗性机制主要为外排泵。相关性分析结果进一步显示,丰度前20的菌属与丰度前20的ARG均有显著相关性(P<0.05),表明微生物群落是影响大黄鱼养殖海域水体中ARG分布的重要因素。本研究为大黄鱼健康养殖及水体ARG控制及消除提供参考依据。

In order to analyze the distribution characteristics of microbial community and antibiotic resistance genes(ARGs)in the water of the large yellow croaker aquaculture area.In this study,water samples from 6 sites of the large yellow croaker intensive aquaculture area were collected through field investigation,and the microbial community and ARGs profiles of water samples were detected and analyzed using Miseq and Hiseq high-throughput sequencing technology.Proteobacteria was the most abundant phylum in all samples,which accounted for 59.62%-75.34%of the sequenced reads.There were significant differences(P<0.05)in the dominated bacterial genera in the water sample of the different large yellow croaker aquaculture area through Ribosomal Database Project(RDP).By BLAST with Comprehensive Antibiotic Resistance Database(CARD).Eight hundred and seventy-two ARGs subtypes belonging to 20 ARGs types were identified,showing the wide-spectrum profiles of ARGs in the water sample of the different large yellow croaker aquaculture area.Statistical analyses revealed that the dominant ARGs types of different water samples were similar,dominated by tetracycline,macrolide and fluoroquinolone resistance genes.Efflux pump was the predominant resistance mechanism in all samples.The co-occurrence pattern between ARGs and microbial taxa showed that there were significant correlations(P<0.05)between the top 20 ARGs and the top 20 bacteria genera.The distribution of microbial community is an important factor affecting the migration and transformation of ARGs in the water samples of the different large yellow croaker aquaculture area.The results of this study provide a theoretical basis for the healthy cultivation of large yellow croaker and the control and elimination of ARGs in water.