, Volume 12, Issue 2, pp 111-119

A simplified method for the purification of human red blood cell glyoxalase. I. Characteristics, immunoblotting, and inhibitor studies

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

Abstract

Glyoxalase I (EC 4.4.1.5) was purified from human red blood cells by a simplified method using S-hexylglutathione affinity chromatography with a modified concentration gradient of S-hexylglutathione for elution. The pure protein had a specific activity of 1830 U/mg of protein, where the overall yield was 9%. The pure protein had a molecular mass of 46,000 D, comprised of two subunits of 23,000 D each, and an isoelectric point value of 5.1. TheK M value for methylglyoxal-glutathione hemithioacetal was 192±8 µM and thek cat value was 10.9±0.2 × 104 min−1 (N = 15). The glyoxalase I inhibitor S-p-bromobenzylglutathione had aK i value of 0.16±0.04 µM and S-p-nitrobenzoxycarbonylglutathione, previously thought to inhibit only glyoxalase II, also inhibited glyoxalase I with aK i value of 3.12±0.88 µM. Reduced glutathione was a weak competitive inhibitor of glyoxalase I with aK i value of 18±8 mM. The polyclonal antibodies were raised to the purified enzyme and were found to react specifically with glyoxalase I antigen by immunoblotting. This procedure gave a protein of high purity with simple low pressure chromatographic techniques with a moderate but adequate yield for small-scale preparations.