Mycobacterium tuberculosis mycolic acid

Isoniazid, the hydrazide of isonicotinic acid was introduced into medical practice for treating tuberculosis in 1953. Isoniazid exhibits bactericidal action on Mycobacterium tuberculosis. It inhibits the synthesis of mycoUc acid, an important component of the cell membrane of mycobacteria. Mycolic acid is specific only to mycobacteria, and it is the cause of the selective toxicity of the drag with respect to these microorganisms. 

Bacteria usually lack polyunsaturated fatty acids but often contain branched fatty acids, cyclopropane-containing acids, hydroxy fatty acids, and unesterified fatty acids. Mycobacteria, including the human pathogen Mycobacterium tuberculosis, contain mycolic acids. In these compounds the complex grouping R contains a variety of functional groups including -OH, -OCH3,... 

As an inhibitor of mycolic acid biosynthesis, compound 43 exhibits activity against strains of Mycobacterium tuberculosis, the causative agent of tuberculosis [79,80,81]. Furthermore,... 

Mycolic acids analysis by thin layer chromatography has been employed by several laboratories worldwide as a method for fast identification of Mycobacterium Mycobacterium tuberculosis strains identified by classical methods were confirmed by their mycolic acid content. 

As families containing the double displacement glycohydrolases can also contain transglycosylases, so CE 1, which contains double-displacement carboxyl esterases, also contains transacylases. Trehalose [a-D-Glcp-(l<->l)-a-D-Glcp] esterified on 06 with mycolic acid plays a role in maintaining the hydrophobic exteriors of the tubercle bacterium Mycobacterium tuberculosis, and the crystal structure of three related mycoloyl transesterases are... 

Figure 12 Cartoon of the arabinogalactan-mycolic acid-modified Mycobacterium tuberculosis peptidogiycan structure. Pyranose forms of sugars are indicated by p, furanose forms of sugars are indicated by f.

The FabH proteins play a major role in specifying product diversity. E. coli FabH is specific for acetyl-CoA as the primer and this organism makes only straight-chain, even-numbered fatty acids. The FabH from gram-positive bacteria that produce branched-chain fatty acids are selective for five- and seven-carbon branched-chain precursors derived from amino acids. In Mycobacterium tuberculosis, the FabH prefers long-chain fatty acids and this organism is characterized by the presence of very long-chain mycolic acids in the membrane. 

George KM, Yuan Y, Sherman DR, Barry CE III. (1995) The biosynthesis of cyclopropanated mycolic acids in Mycobacterium tuberculosis. Identification and functional analysis of CMAS-2. 7 SioZ Chem 270 27292-27298. 

Isoniazid Inhibits mycolic acid synthesis in wall of Mycobacterium tuberculosis. Peripheral neuropathies (can prevent by pretreating with pyridoxine), hepatitis, hepatotoxicity. PO. Widely distributed. N-acetylated, thus, slow acetylators have greater toxicity. Kidney excretion. 

Qureschi, N., and K. Takayama Characterization of the Purified Components of a new homologous series of a Mycolic Acids from Mycobacterium tuberculosis. H 37 Ra. J. Biol. Chera. 253, 5411 (1978). 

There are reports on the mycolic acids of Mycobacterium tuberculosis H. 

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