EFFECT OF SINGLE-POINT MUTATIONS PHE(41)-]HIS AND PHE(143)-]GLU ON FOLDING AND CATALYTIC PROPERTIES OF RECOMBINANT HORSERADISH-PEROXIDASE EXPRESSED IN ESCHERICHIA-COLI

Wild-type recombinant and Phe(41)-->His and Phe(143)-->Glu mutant forms of horseradish peroxidase have been expressed in E. coli and reactivated from inclusion bodies with a yield of about 25%. The purified homogeneous preparations have been studied in the reaction of ABTS oxidation. The effect of mutations on heme entrapment and kinetics of ABTS oxidation demonstrates the essential role of the replaced residues in providing the hydrophobic crevice for the non-covalent heme binding.