Chromogenic Carbamate and Acetal Substrates for Glycosaminidases

The enzyme Dispersin B is a medicinally relevant β-hexosaminidase with potential for use in the treatment of biofilm-related infections. Here we describe the synthesis and evaluation of a p-nitrophenyl glycosyl carbamate and a p-nitrophenyl glycosyl acetal as improved substrates of Dispersin B. The p-nitrophenyl glycosyl carbamate shows substantially improved analytical signal in continuous assays and superior kinetics (kcat/Km 6.1 mM−1 s−1) when compared to the benchmark substrate 4-nitrophenyl N-acetyl-β-D-glucosaminide (kcat/Km 0.021 mM−1 s−1) in measuring Dispersin B activity. The improvements observed are compared to the activity of jack bean β-hexosaminidase toward these substrates.