Isocitrate Lyase As A Target For Anti-tb Drug Discovery Research

Isocitrate Lyase (ICL) is a key rate limiting enzyme in the glyoxylatebypass. Some studies show that: Isocitrate Lyase is the key factor forMycobacterium tuberculosis to maintain the persistent state, and it decides thepersistence characteristic of Mycobacterium tuberculosis. On the other hand,the glyoxylate shunt is not exists in human. Consequently, Isocitrate Lyase is aattractive targets for the development of new anti-tuberculars.We have cloned and expressed the icl-geng of Mycobacteriumtuberculosis H₃₇Rv—Rv0467.After purification by metal chelatingchromatography and four steps chromatographer, produced protein with highpurity was obtained, the purity is above to 90%. The Specific activities are2.821 U/mg and 1.348 U/mg. With the high-through screening modeltargetting to isocitrate lyase of Mycobacterium tuberculosis established in ourlaboratory, 2560 compounds and 8680 microbial fermentation broths werescreened. We found any positive compound. From microbial fermentationbroths, we got 301 positive strains, the positive rate of crude screen is 3.47%.Among them, we chose the fermentation broth of Actinomyces 06-1229 showbetter stability and activity. After cultivation of the strain, a compound 06-1229was isolated and purified from the fermentation. The compound 06-1229 ismicrobial polysaccharide, and the molecular weight is 22773D. The compound06-1229 can't inhibit the growth of Gram-Positive Bacteria, Gram-negativeBacteria and fungi in the aerobic conditions and the anaerobic conditions.