Sialylated oligosaccharides are important components of human milk oligosaccharides (HMOs) that can block adhesion of pathogens to the epithelia in the intestine. Sources of synthetic HMO-mimics is limited due to inefficient and expensive synthesis methods. This paper investigated the synthesis of sialylated lactuloses using the one-pot two-enzyme (OPTE) system.
The OPTE sialylation approach involved α2,3- or α2,6-sialyltransferases and lactulose (OL03995) as the acceptor substrate, to synthesise Neu5Ac-α2,3-lactulose and Neu5Ac-α2,6-lactulose. The resulting novel HMO-mimics demonstrated enhanced anti-microbial activity against S. aureus, compared to non-sialylated lactulose. The proposed mechanism of antibacterial activity is by disrupting the cell membrane and inhibiting growth by disrupting DNA synthesis.
For further information, please refer to the original paper: Zeng et al, 2018.