ETHAMBUTOL INHIBITION OF GLUCOSE-METABOLISM IN MYCOBACTERIA - A POSSIBLE TARGET OF THE DRUG

The addition Of D-arabinose, D-galactose, D-glucosamine, or D-mannose to the growth medium of Mycobacterium smegmatis suppressed the inhibit ory effects of ethambutol both on acetate labeling of cell wall-linked mycolic acids and on the increase in the delipidated cell dry weight. The addition Of D-glucose or D-fructose had no effect. It is proposed that ethambutol inhibits an early step of glucose conversion into the monosaccharides used for the biosynthesis of structurally and biologi cally important cell wall polysaccharides: arabinogalactan, arabinoman nan, and peptidoglycan.