title: Rv1458c: a new diagnostic marker for identification of Mycobacterium tuberculosis complex in a novel duplex PCR assay.
abstract: OBJECTIVE
  We explored the efficiency of Rv1458c, the gene encoding a putative ABC drug transporter specific for the Mycobacterium tuberculosis complex (MTBC), as a diagnostic marker.
  
  
  METHODS
  A 190 bp region of Rv1458c and a 300 bp region of hsp65 were targeted in a novel duplex PCR assay and the results were compared with those for PCR restriction analysis(PRA) using the restriction enzymes NruI and BamHI. Species identification of a subset of the isolates (n=50) was confirmed by sequencing. Clinical isolates of M. tuberculosis (n=426) obtained from clinically suspected patients of pulmonary tuberculosis and mycobacterial (n=13) and non-mycobacterial (n=8) reference strains were included in the study.
  
  
  RESULTS
  The duplex PCR assay correctly identified 320/426 isolates as MTBC and 106/426 isolates as non-tuberculous mycobacteria(NTM). The test was 100 % specific and sensitive when compared with NruI/BamHI PCR restriction analysis and highlighted the use of Rv1458c as a diagnostic marker for MTBC.
  
  
  CONCLUSIONS
  The duplex PCR assay could be developed for use as a screening test to identify MTBC in clinical specimens in peripheral laboratories with limited resources.
authors.affiliation: Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
authors.forename: Kamal
authors.initials: K
authors.lastname: Shrivastava
authors.affiliation: Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
authors.forename: Kushal
authors.initials: K
authors.lastname: Garima
authors.affiliation: Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
authors.forename: Anshika
authors.initials: A
authors.lastname: Narang
authors.affiliation: Dr B R Ambedkar Centre for Biomedical Research (ACBR), University of Delhi, Delhi, India.
authors.forename: Kausik
authors.initials: K
authors.lastname: Bhattacharyya
authors.affiliation: Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
authors.forename: Ekta
authors.initials: E
authors.lastname: Vishnoi
authors.affiliation: Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
authors.forename: Roshan Kumar
authors.initials: RK
authors.lastname: Singh
authors.affiliation: Department of Pulmonary Medicine, Rajan Babu Institute of Pulmonary Medicine and Tuberculosis, Delhi, India.
authors.forename: Anil
authors.initials: A
authors.lastname: Chaudhry
authors.affiliation: Department of Pulmonary Medicine, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
authors.forename: Rajendra
authors.initials: R
authors.lastname: Prasad
authors.affiliation: Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
authors.forename: Mridula
authors.initials: M
authors.lastname: Bose
authors.affiliation: Department of Microbiology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India.
authors.forename: Mandira
authors.initials: M
authors.lastname: Varma-Basil
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics*; D018834:Chaperonin 60 / Q000235:genetics; D005819:Genetic Markers; D006801:Humans; D009161:Mycobacterium / Q000145:classification; D009169:Mycobacterium tuberculosis / Q000235:genetics* / Q000302:isolation & purification*; D009170:Nontuberculous Mycobacteria / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D016133:Polymerase Chain Reaction / Q000191:economics / Q000379:methods*; D012150:Polymorphism, Restriction Fragment Length / Q000235:genetics; D012680:Sensitivity and Specificity; D014376:Tuberculosis / Q000175:diagnosis* / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000382:microbiology
chemical_list: D018528:ATP-Binding Cassette Transporters; D001426:Bacterial Proteins; D018834:Chaperonin 60; D005819:Genetic Markers; C074119:heat-shock protein 65, Mycobacterium