1.2.1.39	-	
1.2.1.39	by gel filtration, 15.9fold with a 0.21% yield	
1.2.1.39	native enzyme 126fold by cross-flow filtration, ultracentrifugation, and anion exchange chromatography, recombinant Strep-tagged enzyme 137fold from Escherichia coli strain DHalpha by affinity chromatography on a Strep-Tactin column	
1.2.1.39	Ni-affinity column chromatography	
1.2.1.39	recombinant N-terminally His-tagged enzyme, NPADH, from Escherichia coli strain BL21(DE3) by nickel affinity chromatography and ultrafiltration to over 90% purity