Isolation of Mycobacterium malmoense from the environment in Zaire

Two strains of mycobacteria isolated from water and soil in Zaire were identified as Mycobacterium malmoense by biochemical tests and lipid analysis. Apart from the previously reported fatty acids characteristic of this species, both strains, as well as 5 clinical isolates of M. malmoense, contained 2,4-dimethyl-docosanoic acid. One of the environmental strains, with a glycolipid pattern II, additionally contained 2-methyltetradecanoic acid. The results confirm that M. malmoense may be subdivided in 2 sub-groups according to its lipid patterns. They also show that M. malmoense can be isolated from the environment which may be the source of the infection.