Studies On The Solution Structure, Dynamics And Functional Analysis Of Ribosomal Protein S1 Of M.Tuberculosis

Since German bacteriologist Robert Koch identified the mycobacterium tuberculosis?M.tb?as the causative agent of tuberculosis?TB?at 1882,TB is still one of the world's highest mortality and morbidity of infectious diseases.The emergence of multi-drug-resistant strains of M.tuberculosismakes the discovery of new drug target and molecular scaffolds a priority.At present,the main strategy is combination for TB treatment,and pyrazinamide?PZA?is an essential pro-drug,which is absorbed into the bacilli and hydrolyzed to antibacterial active form pyrazinamide acid?POA?to inhibit the trans-translation by interaction with ribosomal protein S1?MtRpsA?,in the acid environment.Trans-translation is a important mechanism for activating proteins within signaling pathway,and it's the only pathway available for ribosome rescue in Mycobacterium tuberculosis?MTB?.Therefore,researching the solution structure and dynamics characteristic of MtRpsA contributes to understanding its biological function in M.tb,designing and developing the drugs that target the MtRpsA for TB treatment.MtRpsA comprises 481 amino acids including four uncompleted repeat S1 domains and a helix at C terminus.Previous work reported the crystal structure of the MtRpsA^CTD complex with POA,and the results suggested that POA binding with the fourth S1 domain and C-terminus of RpsA mutations confer PZA resistance.In this paper,we prepared the MtRpsA^CTD 280-438 sample by recombination and isotope labeling techniques,and collected a series of 2D,3D and dynamics spectra for its solution structure calculation and dynamics analysis.Firstly,the spectra were processed by NMRPipe and NMRDraw programs transformation.Secondly,we assigned the 85%atoms chemical shifts by CcpNMR software.Thirdly,the calculation of its solution structure by the chemical shifts and integrate of the spectra ¹⁵N-edited NOESY-HSQC and ¹³C-edited NOESY-HSQC.The structure that obtained from ARIA2&CNS2.1 was similar to the crystal apo structure of the MtRpsA^CTD.The backbone dynamics analysis reveals that the global structure of MtRpsA is relatively rigid except the active site.The binding sites of for the peptide were determined by the chemical shift perturbation approach.This research established the foundation for the development of new drugs.