Metabolomics Analysis Of Evolutionary Lineages,serotypes,Drug-Resistant Strains Of Listeria Monocytogenes

Listeria monocytogenes is a serious food-borne pathogen.The different characteristics of different phenotype strains promote the continuous action of the strains in the food processing environment,and transfer to the food matrix,enter the host body and trigger the outbreak of listeriosis.In the treatment of listeriosis and the prevention of bacterial infections,the use of antibiotics,the lethal environment of food processing and the self-defense of bacterial strains exacerbate the antibiotic resistance of bacterial strains.In view of the different performance characteristics of L.monocytogenes and the increasingly severe strain resistance,there is an urgent need to study the cell metabolomics of the difference characteristics of the strains and the formation of drug resistance.This article takes food-borne L.monocytogenes as the research object.Based on non-target metabolomics technology,the metabolic characteristics relationship among different evolutionary lineages,serotypes and drugresistant strains are studied.The phenotypic characteristics and drug resistance,different evolutionary lineages and serotypes strains were explained.The main contents are as follows:1.The correlation between different characteristics and metabolic profiles of strains from different evolutionary lineages was studied.The results show that there are metabolomics differences between lineage ? and lineage ? strains.The differential metabolites of the two lineages strains are classified into 33 species,mainly amino acids and nucleotides.The up-regulation of the expression of TMP,uridine and UMP in the lineage II strains is closely related to the growth and reproduction of the strains.The down-regulation of the expression of citric acid and isocitrate makes the energy metabolism of the lineage I strains lower than that of the lineage II strains.2.The correlation between the difference characteristics of different serotype strains and the metabolic profile is found.The results show that there are differences in metabolomics between strains of different serotypes.The four serotype strains have identified 78 different compounds,mainly divided into amino acids and nucleotides.Through enrichment analysis of metabolic pathways,it was found that among the 4b and 1/2b serotype strains,the cell lysis rate of 4b strain was higher than that of other serotype strains,which may be related to the up-regulation of pyridoxine by the strain.The strong pathogenicity of 4b strain may be related to the production of high uric acid in the cellular purine metabolism pathway.In the 1/2a and 1/2c serotype strains,the synthesis of DNA and RNA in the cells of the 1/2a serotype strain is inhibited due to the down-regulation of nucleic acid precursor substances.3.The relationship between sulfonamides drug resistance and the metabolic profile of isolates was studied.The results show that the cells had obvious metabolic characteristics before and after the strain produced trimethoprim-sulfamethoxazole(SXT)resistance.In total,the intracellular metabolites of 22 different drug-resistant and sensitive strains were identified.The analysis found that when the strain developed resistance to the SXT,the intracellular oxidative stress response was significantly increased,and the synthesis of peptides and/or proteins was significantly reduced.In addition,the strain regulates intracellular transport,protein function and signal transduction are also affected by SXT.The research results of this paper indicate the substances formed by the main differences of the three phenotypes of the strains and their changing trends,which provide theoretical support for the study of the phenotypic characteristics of the strains.