Cloning and expression of aceA gene encoding isocitrate lyase from Mycobacterium tuberculosis

The enzyme isocitrate lyase (ICL) reversibly catalyses the conversion of is ocitrate to glyoxylate and succinate in the glyoxylate bypass of the tricar boxylic acid (TCA) cycle. We cloned the Mycobacterium tuberculosis aceA gen e encoding ICL using polymerase chain reaction (PCR). Restriction mapping a nd sequencing confirmed the cloned gene to be M. tuberculosis aceA gene. Th e cloned gene consists of 2300 nucleotides encoding a protein of 765 amino acids. The cloned fragment has a high degree of similarity of aceA gene of M. leprae. Expression of the cloned gene was confirmed by assay of the enzy me.