Studies on the Metabolism of Mycobacterium Tuberculosis Vi

Abstract

There is no general agreement concerning the oxidation of many of the Krebs' cycle intermediates and precursors by tubercle bacilli. Nakamura (1938) using classical Warburg techniques reported that of 25 substrates tested only glycerol and glutamic acid stimulated respiration. Some of the materials found inactive were glucose, succinic, malic, and citric acids. Cutinelli (1940a,b,c) found that succinic, fumaric, malic, and pyruvic acids caused only small increases in oxygen uptake. Edson and Hunter (1943) confirmed Cutineili's results with pyruvate and succinate using the avirulent Ti strain of Mycobacterium tuberculosis var. hominis and claimed that citrate was not oxidized. Bernheim (1942) reported that glucose and lactic, pyruvic, and succinic acids were not oxidized by strains H37 and B1 while Oginsky, Smith, and Solotorovsky (1950) reported that with the avian Kirchberg strain pyruvic, oxalacetic, and pyruvic plus oxalacetic acids were oxidized slowly. Other members of the citric acid cycle, cis-aconitate, citrate, a-ketoglutarate, succinate, and fumarate, did not permit significant increases in oxygen uptake over a period of 270 minutes. Geronimus and Birkeland (1951) found that avirulent mycobacteria oxidized lactic and low molecular weight fatty acids more rapidly than pathogenic strains. Edson (1951) in a review of the intermediary metabolism of the mycobacteria attempted to integrate most of the scattered information relative to this problem. He came to the conclusion that there were few, if any, clues to the understanding of the intermediary changes.

THE OXIDATION OF COMPOUNDS RELATED TO THE TRICARBOXYLIC ACID CYCLE BY WHOLE CELLS AND ENZYME PREPARATIONS OF MYCOBACTERIUM TUBERCULOSIS VAR. HOMINIS

“…Both organisms contain enzymes which oxidize intermediates of the tricarboxylic acid cycle. However, whole cells of the H37Ra strain appear to be more permeable to these intermediates (Holmgren, Millman, and Youmans, 1954) than whole cells of the H37Rv strain (Youmans and Youmans, 1953).…”