Effect Of Antibiotics On Carbon Fixation Microorganisms In Karst Water

Karst dynamic system is an important part of global carbon cycle,which determines the direction and flux of global carbon cycle to some extent.The most characteristic karst areas in the world are distributed in southwest China,which is of great research value.However,due to the unreasonable discharge of human production and life,antibiotics have been polluting the karst water in this area for a long time,which affects the carbon cycling in which microorganisms participate.The study on the effect of antibiotics on the carbon fixation pathways in microorganisms in karst water will be helpful to understand the disturbance of human activities on the carbon cycle involved by microorganisms.In this paper,the microbial community of typical karst water samples in southwest China was taken as the research object,and the response mechanism of carbon fixation microorganisms to antibiotics was discussed from the perspectives of community structure,carbonic anhydrase and resistance genes by using metagenomic analyses.The main results of this paper are as follows:(1)Microbial community was divided into 6 ecological clusters through analysis of microbial co-occurrence network,among which the relative abundance of 4 ecological clusters was significantly correlated with antibiotics,and antibiotic resistance genes may be an important reason for such changes in relative abundance.(2)The carbon fixation forms of different microbial ecological clusters in karst water are diverse,and the species with carbonic anhydrase gene are important microbial species in karst water.The effect of antibiotics on carbonic anhydrase is also an important factor to change the fate of carbon cycle.(3)The hydroxypropionate-hydroxybutyrate cycle(M00375)and the reductive acetyl-Co A pathway(M00377)are important carbon fixation pathways for carbon fixation microorganisms in the study area,reflecting the strategies of different ecological clusters to resist antibiotic.This study provides a reference for the influence of long-term antibiotic pollution in karst water on the carbon cycle process involving microorganisms,and also provides a scientific basis for the supervision and treatment of environmental risks caused by antibiotics.