p-Nitrophenyl alpha-D-glucopyranoside, a new substrate for glucansucrases.

p-Nitrophenyl alpha-D-glucopyranoside has been shown to be a substrate for the glucansucrases of various strains of Leuconostoc mesenteroides and Streptococcus mutans. The products from a digest of p-nitrophenyl alpha-D-glucopyranoside with L. mesenteroides B-512F dextransucrase were found to include dextran, a series of p-nitrophenyl isomaltodextrin glycosides, and p-nitrophenyl nigeroside. The kinetics of the reaction were non-Michaelis-Menten, possibly because p-nitrophenyl alpha-D-glucopyranoside has a dual role in the reaction as both a D-glucosyl donor and acceptor.