Identification & differentiation of Mycobacterium avium & M. intracellulare by PCR- RFLP assay using the groES gene.
OBJECTIVE
We report a new polymerase chain reaction (PCR) - restriction fragment length polymorphism (RFLP) assay using mycobacterial groES as a target to identify Mycobacterium avium and M. intracellulare in clinical samples.


METHODS
The assay was standardized using M. avium and M. intracellulare standard strains obtained from ATCC and was tested with 45 M. avium-M. intracellulare complex (MAC) clinical isolates (Of which 31 were from HIV(+) individuals). The standard and clinical strains were typed with HPLC based mycolic acid fingerprinting.


RESULTS
Three polymorphisms (BamHI, BstNI and HgaI) were identified for inter-species differentiation among standard strains; of which, only HgaI was found to be useful in clinical isolates. Of the 45 isolates, 25 were M. avium and 20 were M. intracelluare. MAC isolates, which could not be differentiated by HPLC analysis, were also typed by this method.


CONCLUSIONS
The use of mycobacterial groES as a PCR-RFLP target for M. avium and M. intracellulare is a simple and rapid method that can complement HPLC in their differentiation.
Aravindhan
V
V
Tuberculosis Research Centre , Chennai, India.
Sulochana
S
S
Narayanan
Sujatha
S
Paramasivam
C N
CN
Narayanan
P R
PR
D000942:Antigens, Bacterial / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D018835:Chaperonin 10 / Q000235:genetics*; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D005798:Genes, Bacterial; D006360:Heat-Shock Proteins / Q000235:genetics; D006801:Humans; D009162:Mycobacterium avium / Q000235:genetics* / Q000302:isolation & purification; D015269:Mycobacterium avium Complex / Q000235:genetics* / Q000302:isolation & purification; D016133:Polymerase Chain Reaction / Q000379:methods; D012150:Polymorphism, Restriction Fragment Length; D013045:Species Specificity
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D018835:Chaperonin 10; D017931:DNA Primers; D004269:DNA, Bacterial; D006360:Heat-Shock Proteins; C058749:groES protein, Mycobacterium tuberculosis