The peroxidases are a ubiquitous subset of enzymes found in both the animal and plant kingdoms. Of all the peroxidases, the majority of research has focussed on the Class III Horseradish Peroxidase (E.C. 1.11.1.7). The basic form, HRP-C, is the most common and is utilised in this study. Recombinant HRP-C was first expressed over fifteen years ago; however, its production has been plagued by the formation of inclusion bodies and low yields. In this present study, the HRP gene and a PelB leader sequence were directionally cloned to form a fusion protein, expressed to the bacterial periplasmic envelope. By manipulating subsequent expression conditions, fully functional HRP was successfully produced, with the inclusion of a poly-Histidine tag permitting single step purification. Site directed mutagenesis was utilised to probe the stability of the recombinant enzyme. Two methodologies were employed to select residues for mutation, initially a rational approach, based on previous knowledge proposed 16 mutations. The second method based on a peroxidase sequence alignment utilising novel bioinformatic software, proposed 6 mutations. These mutants were generated, expressed and purified via optimised conditions. All mutants were characterised based on thermal, solvent and H2O2 stabilities, as well as kinetic analysis. Important stabilising roles for Glutamic Acid 238, Glutamine 106 and the helical secondary structure within the HRP protein were noted. Peroxidase structure evolution could be followed via a novel archetype peroxidase sequence generated. Mutations, which increased hydrogen bonding in the Lysine 232/Lysine 241 axis, improved stability. Genetic engineering was also employed to generate a recombinant HRP-C that permitted simple directed immobilisation (one triple mutant and one pentuple mutant), allowing maximal accessibility to the enzymes’ active site. Improved immobilisation capacity was achieved, however, at the cost of free and immobilised stability. Application o f wildtype recombinant HRP-C to screen-printed and etched platinum electrode biosensors was investigated. Improved direct electron transfer was noted for recombinant HRP over plant HRP for both configurations.