Abstract: Mycobacterium tuberculosis harbors three inteins in three critical proteins. Post-translational removal of the inteins is required for function of the proteins.Thus, inteins are potential targets for antimycobacterial agents. It is very important to develop a high throughput screening system for the isolation of antimycobacterial drugs that interfere with protein splicing. Therefore, the RecA intein coding sequence of Mycobacterium tuberculosis was inserted into kanamycin-resistance gene so that functional antibiotic resistance was restored upon protein splicing. Western Blot and kanamycin plate assay showed that the kanamycin resistance in LB plate was in accordance with the intein splicing efficiency, which was capable of screening system for intein inhibitors. To examine the utility of this screen system, the growth of E.coli transformed with plasmids containing kanamycin-intein fusions was significantly slowed by cisplatin, which showed that cisplatin toxicity could be suppress protein splicing by intein overexpression.

Key words: Mycobacteriun tuberculosis, intein, protein splicing, kanamycin resistance