A Pasteurella multocida sialyltransferase displaying dual trans-sialidase activities for production of 3′-sialyl and 6′-sialyl glycans.

Highlights: [•] PmST, a Pasteurella multocida sialyltransferase expressed in Escherichia coli exhibited both α-2,3- and α-2,6-trans-sialidase activities. [•] Optimum conditions were identified for maximum production of 3′- and 6′-sialyllactoses by PmST-catalyzed trans-sialylation using casein glycomacropeptide as the donor for sialic acid. [•] The regioselective synthesis of sialyllactose could be achieved by regulating reaction time. [•] The kinetic parameter for α-2,6-trans-sialidase activity of PmST was estimated. [•] PmST catalyzed α-2,3 as well as α-2,6 sialylation of prebiotic galactooligosaccharides. [ABSTRACT FROM AUTHOR]