Occurrence Of Antibiotic Resistance Genes And Their Relationship With New Fecal Indicator Bacteria In Poyang Lake Basin

Object: Antibiotic resistance genes had been considered as Emerging environmental contaminants.Drug resistance caused by Antibiotic resistance bacteria aroused widespread concern in the world.This study aims to explore the distribution of antibiotic resistance genes in Poyang Lake Basin and their association with new types of fecal contamination indicator bacteria.Methods: Six representative sites in the Poyang Lake Basin were selected and water samples were continuously collected during the wet season(May and June)and dry season(November,December,January and February).Each site collected water once a month.23 antibiotic resistance genes(9 types)and 3 novel fecal contamination indicators were detected with Fluorescence quantitative PCR technology including tetracyclines(tetB,tet C,tetM,tetQ,tet X),sulfonamides(sul1,sul2,sul3),aminoglycosides(aph(2’’)-Id,aadA,aac(6’)-Ib),β-lactams(blaTEM,ampC,blaNDM-1),macrolides(ermA,ermB),chloramphenicol(catA,cmlA),antituberculosis antibiotic(katG,rpoB1),trimethoprim(dfrA1),vancomycin(vanA),colistin(mcr-1),general Bacteroides,human specific Bacteroide and bovine specific Bacteroide.Temporal and spatial distribution patterns of antibiotic resistance genes and fecal contamination indicators were statistically analyzed and the correlation between them was analyzed.Results: The results showed that all the 22 resistance genes were found.The detection rates of sul1,sul2,blaTEM,tetC,aac(6 ’)-1b,aadA and rpoB1 were 100%,97.2%,97.2%,94.4% 94.4%,88.9% and 83.3%.The detection rates of general bacteroides,Human specific bacteroides and Beef specific bacteroides were 97.20%,97.20% and 66.70% respectively.In terms of time distribution,20 resistance genes and 3 types of bacteroides did not show significant differences between wet season and dry season.In terms of spatial distribution,the absolute abundance of 23 resistant genes and 3 types of bacteroides in Qingshanzha was significantly higher than that of Tushan,Guanniaotai,Wucheng,Xingzi and Dukou.22 resistance genes weresignificantly positively correlated with general Bacteroides.20 resistance genes were significantly positively correlated with human specific Bacteroide.12 resistance genes were significantly positively correlated with bovine specific Bacteroide.Conclusion: Poyang Lake Basin is contaminated by many kinds of Antibiotic resistance genes and faeces.The sulfa resistance genes are the dominant resistance gene in Poyang Lake Basin.Human faecal contamination is one of main sources of fecal pollution in the Poyang Lake Basin.Antibiotic resistance genes and stool pollution in the upstream river Ganchang Nanchang section was significantly higher than the lake,but pollution in the lake has no significant difference.Human and animal excrement contamination may be one of the main causes of Antibiotic resistant gene contamination in the Poyang Lake Basin.