Multi-omics Analysis Of Resistance Mechanisms Of Mycobacterium Tuberculosis Resistant To Capreomycin

BackgroundTuberculosis(TB)is a chronic infectious disease caused by Mycobacterium tuberculosis,which can affect many human organs.Due to the long treatment cycle of tuberculosis and the lack of new and effective drugs,multi-drug resistant tuberculosis(MDR-TB)has emerged,making it more difficult to eliminate TB.Capreomycin(CAP)is one of the commonly used second-line drugs for TB.CAP resistance is associated with the gene tlyA.However,the specific mechanism of drug resistance has not yet been clarified.ObjectiveBy using a multi-omics study method,a comparative analysis of capreomycin-resistant strains and wild-type strains was carried out,and multi-omics results were combined to identify possible drug-resistant pathways.MethodThe drug-resistant gradient was used to induce stable drug-resistant Mycobacterium tuberculosis,and the capreomycin resistance related genes tlyA and rrrs were sequenced.Further performance cross-resistance experiments.The selected drug-resistant strains and wild-type strains were analyzed for differences in genome,proteomics and metabolomics,and the results were verified to further explore possible drug resistance pathways.ResultWe induced a stable CAP resistance model in vitro,including tlyA deletion mutations and point mutations.Through cross-resistance experiments,the phenomenon of inconsistency between clinical and CAP-induced mutations in CAP was explained,and the most relevant gene for CAP resistance was tlyA.Through proteomics experiments,we found high expression of ribosomal protein in CAP~r strain.In combination with published studies,it is speculated that microbes will act as a compensatory mechanism for antibiotics in ribosomes by high expression of ribosomal proteins;combined with multi-omics experiments and virulence and phenotypic experimental results,we conclude that:The tlyA mutant CAP-resistant strains(CAP~r1(MIC>40?g/ml)and CAP~r2(MIC>10?g/ml))have significant differences in protein and metabolites,suggesting that the tlyA deletion mutation has more complex tolerance.Pharmacokinetics;multi-omics results and phenotypic experiments indicate that the drug resistance of CAP~r1 strain may be related to glycerophospholipid metabolism and glycerolipid metabolism pathway;proteomic experiments show that AdoMet-MT protein expression in CAP~r1 is decreased,We speculate,decreased expression of S-adenosyl-L-methionine-dependent methyltransferase(AdoMet-MT)-related protein reduces methylation of donor S-adenosylmethionine(SAM),which also inhibits normal Methylation.ConclusionCollectively,our results demonstrate that CAP resistance in Mtb is caused by a combination of multiple resistance mechanisms,not just by tlyA mutations.It is beneficial for us to better understand Mtb and its tolerance of CAP,which may be helpful for the development of novel therapy approaches.