Lysozyme-mediated p-Nitrophenyl Penta-N-acetyl-β-chitopentaoside Production in Aqueous-dimethylsulfoxide Solvent System, as a Substrate for a Lysozyme Assay

Abstract

PNP-(GlcNAc)₅, which is available as a substrate of a lysozyme assay, was efficiently synthesized by transfer of the tetra-N-acetyl-chitotetraosyl residue to the 4-position of PNP-GlcNAc using lysozyme in an aqueous solution containing DMSO in a high concentration. The use of an aqueous DMSO system in this reaction not only ensured a sufficient solubility of PNP-GlcNAc substrate, but also resulted in the high yield of PNP-(GlcNAc)₅. PNP-(GlcNAc)₅ insolubilized from the reaction mixture was directly obtained in a high state of purity by washing with aqueous methanol without using any column chromatographic separation.