Mycobacterium bohemicum sp. nov., a new slow-growing scotochromogenic mycobacterium.

A new, slow-growing, scotochromogenic mycobacterium was isolated from sputum of a 53-year-old patient with Down's syndrome suffering from tuberculosis. Growth occurred at temperatures between 25 and 40 degrees C with an optimum at 37 degrees C. This strain had surprisingly few enzymic activities (only positive for 68 degrees C heat-stable catalase and weakly positive for urease) and was sensitive to prothionamide, cycloserine, clarithromycin, gentamicin and amikacin but showed resistance to isoniazid, streptomycin, ethambutol, rifampin and ciprofloxacin. These characteristics assign this organism to a novel mycobacterial species characterized by a unique 16S rDNA nucleotide sequence. The name Mycobacterium bohemicum sp. nov. is proposed for this new, slow-growing, scotochromogenic mycobacterium. The type strain is DSM 44277T.