Patent ID: 8907062

Claim:
A method of producing and purifying recombinant mitochondrial targeting signal (MTS)-truncated coenzyme Q5 homolog (COQ5) protein in non-denaturing conditions, comprising the steps of: providing an Escherichia coli ( E. coli ) host cell transformed with an expression vector containing a DNA fragment that encodes the recombinant COQ5 protein; inducing the expression of the recombinant COQ5 protein in the E. coli host cell; lysing the bacterial cells with a lysis buffer comprising lysozyme and deoxyribonuclease I (DNase I); pre-treating the bacterial cell lysate with less than 0.2% of an ionic detergent; centrifuging the cell lysate for removing insoluble proteins or debris and collecting the supernatant containing the recombinant COQ5 protein; and applying the supernatant to nickel-nitrilotriacetic acid (Ni-NTA) beads under native conditions that lack exposure to urea to obtain purified recombinant COQ5 protein.