A New Staining Method for Lyases Catalyzing Cleavage of a C–S Bond in Sulfur-containing Compounds after Polyacrylamide Gel Electrophoresis

We developed a rapid and simple staining method for lyases catalyzing cleavage of a C–S bond in sulfur-containing compounds after polyacrylamide gel electrophoresis. This method was based on the finding that 3-(4′,5′-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) was readily reduced by various thiol compounds in the presence of phenazine methosulfate to yield formazan. Cystathionine γ-lyase [EC 4.4.1.1] and cystine lyase were quickly detected by this staining method after polyacrylamide gel electrophoresis. The staining method developed here may be applicable to a wide range of lyases catalyzing cleavage of a C–S bond as a quick and simple method for detection of their activities on polyacrylamide gels.