PROPAGATION OF MYCOBACTERIUM-LEPRAEMURIUM ON SUPPLEMENTED MINIMAL MEDIUM AND ITS EXPERIMENTAL PATHOGENESIS

The splenic tissue of a mouse experimentally infected with M. lepraemu rium (Hawaiian strain, M-65) and developing 'rat leprosy', yielded a p ure culture of an acid - fast bacterium having all the characteristics of M. lepraemurium on mineral salt minimal. medium supplemented with simple sources of C and N, e.g., NH4 -salts, liquid paraffin, urea, ge latin etc. This could be maintained, by serial passages in vitro with good growth. Its indefinite propagation with tissue - free washed, sma ll inoculum on complex media including Ogawa medium was difficult, and its serial sub-culture was practically impossible. The in vitro isola te from supplemented minimal medium could produce pathological lesions in mice typical of rat leprosy.