Studies on Pathogenic Leptospirae

V Growth of Pathogenic Leptospirae on Lipid Fractions Obtained from Acid-Fast Bacilli

Abstract

Growth of the pathogenic leptospirac, Leptospira canicola, strain Utrecht and L. icterohaemorrhagiae, strain Mikawajima, in modified Korthof's basal medium containing various lipid fractions obtained from Mycobacterium smegmatis and M. tuberculosis strain Aoyama B in place of rabbit serum, was examined. Growth of L, canicola, strain Utrecht was supported by all mycobacterial lipid fractions. The growth of L. icterohaemorrhagiae strain Mikawajima was supported by mycolic acid and mycolic acid-containing fractions, such as chloroform extract, purified wax, wax C, wax D, cord factor, bound lipid B and bound lipid D, but not by the fractions containing unsaturated fatty acids, such as alcohol-ether extract, and the bound lipids A and C. It is of interest that leptospiral growth was stimulated by a higher molecular fatty acid such as mycolic acid. Furthermore, distinct differences in Tween 80 requirement were found between L. canicola, strain Utrecht and L. icterohaemorrhagiae, strain Mikawajima.