“…The replacement of an amino acid in the NADH binding site of InhA apparently results in INH resistance, preventing the inhibition of mycolic acid biosynthesis (Zhang YM, et al, 2006). Various genetic mutations have been observed to occur usually between codons 138 and 328 (Ramaswamy S, et al, 1998). The Ser-315-Thr mutation is most frequent and found in about 40% of all INH-resistant strains (Marttila HJ, et al, 1998, Zhang YM, et al, 2006.…”