Thermostability Measurement of an α-Glucosidase Using a Classical Activity-based Assay and a Novel Thermofluor Method α-glucosidases (including maltases and isomaltases) are enzymes which release glucose from a set of α-glucosidic substrates. Their catalytic activity, substrate specificity and thermostability can be assayed using this trait. Thermostability of proteins can also be determined using a high-throughput differential scanning fluorometry method, also named Thermofluor. We have shown that Thermofluor can also be applied to predict binding of substrates and inhibitors to a yeast α-glucosidase. The methods described here in detail were used in Viigand et al., 2016.