Optimization of Purification Protocol for Taq DNA Polymerase used in Polymerase Chain Reaction

Abstract

Protein purification plays a significant role in the production of therapeutic proteins, otherwise known as protein drugs. Although 380 protein drugs are currently marketed and used to treat a wide range of illnesses, the protocol for protein purification varies slightly amongst pharmaceutical companies. Thus, this study was undertaken to optimize some parameters involved in protein purification. Taq DNA polymerase was inserted into and grown in an E. coli. cell culture, isolated using ion gradient chromatography and a fraction collector, and assayed using polymerase chain reaction. The concentration of isopropyl-β-D-1-thiogalactopyranoside (IPTG) used to induce the bacterial culture and the column flow rate in chromatography were tested and adjusted to optimize the protein purification protocol and determine their effect on both the quantity of the purified protein collected and the enzymatic activity of the purified protein. It was discovered that an IPTG concentration of 0.1675 mM and a column flow rate of 2 mL/min resulted in the highest protein expression. It was concluded these values optimized the protein purification protocol both economically and in terms of production quantity.