Characterization of dimethyl sulphoxide reductase from brewing yeast

Abstract

Dimethyl sulphoxide (DMSO) reductase is present in all brewing yeast strains tested, but is more readily detectable using activity stains on polyacrylamide gels than through direct spectrophotometric assay of crude extracts. The enzyme is detectable at higher activities in yeast cultivated at lower temperatures and this is because of increased expression of the primary gene that codes for the enzyme in yeast, MXR1. DMSO somewhat increases enzyme expression, notably in lager yeast by up to 70%, whereas methionine suppresses it. Both ale and lager strains produce enzymes of ~100,000 in molecular weight, but ion exchange chromatography divides the activity for both ale and lager yeasts into two fractions with distinct properties (heat tolerance, pH optimum, kinetic parameters). Copyright © 2017 The Institute of Brewing & Distilling

The Horace Brown Medal. Forever in focus: researches in malting and brewing sciences

“…This led to our work demonstrating that yeast does indeed convert DMSO (which we showed to be present in malt, especially after curing) into DMS . I demonstrated that the enzyme involved was methionine sulfoxide reductase ( , see also ). This is an enzyme present in many eukaryotes which serves the function of recycling methionine sulfoxide to methionine and thereby restoring its functionality.…”