Molecular Dynamics Investigation of the Role of Residues D137 and S315 to INH Binding in KatG

Abstract

Introduction Abstract Introduction Materials and Methods Results Discussion References Then Mycobacterium tuberculosis (Mtb) catalase-peroxidase (KatG) protein is a bi-functional enzyme that exists as a homodimer of 80-kDa subunits1 (Figure 1). Each subunit binds one heme cofactor, exhibiting a binding pocket environment and sequence homology that classifies the enzyme as a class I peroxidase. KatG also contains a covalently-linked three amino acid adduct in the distal heme pocket, comprised of W107, Y229 and M255 that is not found in monofunctional peroxidases. Mutagenesis studies have indicated that the adduct is necessary for catalase but not peroxidase activity. Existing crystal structures of KatG show adduct formation in each case and a high degree terti ...