Synthesis of gold glyconanoparticles: Possible probes for the exploration of carbohydrate-mediated self-recognition of marine sponge cells

The first step in marine sponge cell recognition and adhesion operates via a calcium-dependent proteoglycan-proteoglycan interaction. For the marine sponge Microciona prolifera, one of the carbohydrate epitopes involved in the proteoglycan self-recognition is a sulfated disaccharide [GlcpNAc3S(beta1-3)Fucp]. Earlier surface plasmon resonance studies have demonstrated that the proteoglycan self-recognition can be mimicked with synthetic (beta-D-GlcpNAc-(1-->3)-alpha-L-Fucp-(1-->O), when multivalently presented by conjugation with bovine serum albumin. Here, the straightforward synthesis of water-soluble gold glyconanoparticles coated with the glycosides (beta-D-GlcpNAc3S-(1-->3)-alpha-L-Fucp(1-O)(CH2)(3)S(CH2)(6)SH, beta-D-GlcpNAc3S-(1-->3)-beta-L-Fucp-(1-->O)(CH2)(3)S(CH2)(6)SH, beta-D-GlcpNAc3S-(1-->O)(CH2)(3)S(CH2)(6)SH, alpha-L-Fucp-(1-->O)(CH2)(3)S(CH2)(6)SH, beta-D-GlcpNAc3S-(1-->3)-alpha-L-Galp-(1-->O)(CH2)(3)S(CH2)(6)SH, beta-D-GlcpNAc-(1-->3)-alpha-L-Fucp-(1-->O)(CH2)(3)S(CH2)(6)SH, and beta-D-Glcp3S-(1-->3)-alpha-L-Fucp-(1-->O)(CH2)(3)S(CH2)(6)SH is presented. Such supramolecular structures are excellent probes for studying carbohydrate-carbohydrate interactions by transmission electron microscopy, thereby generating information on the molecular level about the role of different functionalities in the self-recognition process. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).