A mutation in the 65,000 Dalton heat shock protein gene, commonly used for molecular identification of non-tuberculous mycobacteria, leads to the misidentification of Mycobacterium malmoense as Mycobacterium marinum.
We describe a case of a Mycobacterium isolated from a patient with cervical lymphadenitis which was initially identified by hsp65 RFLP as Mycobacterium marinum. Sequence analysis of the hsp65 DNA fragment and the 16S rDNA signature sequence, however, led to the identification of Mycobacterium malmoense. A point mutation in one of the restriction sites had shifted the M. malmoense typical RFLP pattern to the M. marinum specific RFLP pattern. As a consequence, care should be taken when identifying mycobacteria with the use of one molecular technique, only.
Department of Hygiene and Medical Microbiology, Hygiene-Institute, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany. di5@ix.urz.uni-heidelberg.de
Oliver
O
Nolte
Heike
H
Haag
Bernhard
B
Häfner
D015373:Bacterial Typing Techniques / Q000379:methods*; D006360:Heat-Shock Proteins / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D008970:Molecular Weight; D009161:Mycobacterium / Q000235:genetics* / Q000302:isolation & purification*; D019910:Mycobacterium marinum / Q000235:genetics* / Q000302:isolation & purification*; D017354:Point Mutation / Q000235:genetics*; D015203:Reproducibility of Results; D012107:Research Design; D017422:Sequence Analysis, DNA
D006360:Heat-Shock Proteins