title: Comparative proteomic analysis of sequential isolates of Mycobacterium tuberculosis from a patient with pulmonary tuberculosis turning from drug sensitive to multidrug resistant.
abstract: OBJECTIVE
  Tuberculosis is a major health problem in India, and the emergence of multidrug resistant (MDR) and extensively drug resistant (XDR) strains of Mycobacterium tuberculosis (Mtb) has further complicated the situation. Though several studies characterizing drug sensitive and drug resistant strains are available in literature, almost all studies are done on unrelated strains. Therefore, the objective of this study was to compare the proteomic data of four sequential isolates of Mtb from a single patient who developed MDR-TB during the course of anti-tuberculosis therapy (ATT).
  
  
  METHODS
  In this study, using two-dimensional (2D) gel electrophoresis and MALDI-TOF mass spectrometry, we compared and analyzed the cell lysate proteins of Mtb sequential clinical isolates from a patient undergoing anti-TB treatment. The mRNA expression levels of selected identified proteins were determined by quantitative real-time polymerase chain reaction (qRT-PCR).
  
  
  RESULTS
  The genotypes of all four isolates remained homologous, indicating no re-infection. The initial isolate (before treatment) was sensitive to all first-line drugs, but the consecutive isolates were found to be resistant to isoniazid (INH) and rifampicin (RIF) and developed mutations in the katG, inhA and rpoB. the intensities of 27 protein spots were found to be consistently overexpressed in INH and RIF resistant isolates. The most prominent and overexpressed proteins found during the development of drug resistance were GarA (Rv1827), wag31 (Rv2145c), Rv1437 and Rv2970c.
  
  
  CONCLUSIONS
  This preliminary proteomic study provides an insight about the proteins that are upregulated during drug resistance development. These upregulated proteins, identified here, could prove useful as immunodiagnostic and possibly drug resistant markers in future. However, more studies are required to confirm these findings.
authors: Amit
authors: A
authors: Singh
authors: Krishnamoorthy
authors: K
authors: Gopinath
authors: Prashant
authors: P
authors: Sharma
authors: Deepa
authors: D
authors: Bisht
authors: Pawan
authors: P
authors: Sharma
authors: Niti
authors: N
authors: Singh
authors: Division of Clinical Microbiology & Molecular Medicine, Department of Laboratory Medicine, All India Institute of Medical Sciences, New Delhi, India.
authors: Sarman
authors: S
authors: Singh
mesh_terms: D000328:Adult; D000995:Antitubercular Agents / Q000627:therapeutic use*; D001426:Bacterial Proteins / Q000378:metabolism*; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D006801:Humans; D008297:Male; D009169:Mycobacterium tuberculosis / Q000378:metabolism*; D040901:Proteomics; D060888:Real-Time Polymerase Chain Reaction; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014397:Tuberculosis, Pulmonary / Q000188:drug therapy / Q000378:metabolism*; D055815:Young Adult
chemical_list: D000995:Antitubercular Agents; D001426:Bacterial Proteins