From the city of Malmö, Sweden where the strain used for the description was isolated from patients.

Gram-positive, nonmotile, acid-fast and coccoid to short rods.

• Environmental reservoir: soil and water.

Colony characteristics

• Smooth and nonpigmented colonies, growth below the surface of semisolid agar medium after deep inoculation (as seen with M. bovis), 0.9 - 1.7mm in diameter.

Physiology

• Growth on inspissated egg medium and oleic acid-albumin agar at a temperature range of 22 °C-37 °C requires over 1 week.
• Susceptible to ethambutol, ethionamide, kanamycin and cycloserine.

Differential characteristics

• Antigenic structure: seroagglutination demonstrates a single serovar distinct from that of other species.

• Usually infects young children with cervical lymphadenitis or adults with chronic pulmonary disease, (mostly with previously documented pneumoconiosis).
• Rarely causes extrapulmonary diseases and disseminated infections
• Biosafety level 2
• The first case of infectious endocarditis by M. malmoense was reported in 2020 in Cali, Colombia. The patient was a 61-year old woman with a history of biological mitral valve replacement due to rheumatic disease, dermatomyositis and rheumatoid arthritis in management with methotrexate, chloroquine, and prednisolone.^[1]

• First isolated from sputum and biopsy specimens with pulmonary disease in Malmö, Sweden.

Strain ATCC 29571 = CCUG 37761 = CIP 105775 = DSM 44163 = JCM 13391 = NCTC 11298.

• Schroder, K. H.; Juhlin, I. (1977-07-01). "Mycobacterium malmoense sp. nov". International Journal of Systematic Bacteriology. 27 (3): 241–246. doi:10.1099/00207713-27-3-241.

• Type strain of Mycobacterium malmoense at BacDive - the Bacterial Diversity Metadatabase