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A strategy for the immobilization of the enzyme 2-deoxy-d-ribose-5-phosphate aldolase (DERA) is presented via spray-coating on membrane support material to generate an enzymatically active membrane which can be used in continuously run synthesis modules. A functional, water-soluble copolymer containing addressable units to covalently bind DERA is mixed with the enzyme, followed by spray-coating of the mixture onto polyacrylonitrile/polyethylene imine- (PAN/PEI) membranes and a subsequent post-processing to stabilize the coating. Confirmation of successful immobilization was achieved by atomic force microscopy (AFM) imaging and assessment of retained enzyme activity. Through variation of relevant parameters, improvements in stability and activity were seen, which formed the basis for the following optimization by Design-of-Experiment (DoE). A first fractional factorial design yielded additional performance improvements and important insights into the impacts of experimental parameters and their interaction. A second full factorial design did not result in further improvements, but validated the results of the first design.

Glycan‐protein interactions are essential biological processes with many disease‐related modulations and variations. One of the key proteins involved in tumor progression and metastasis is galectin‐3 (Gal‐3). A lot of effort is put into the development of Gal‐3 inhibitors as new therapeutic agents. The avidity of glycan‐protein interactions is strongly enhanced by multivalent ligand presentation. Multivalent presentation of glycans can be accomplished by utilizing glycopolymers, which are polymers with pendent glycan groups. For the production of glycopolymers, glycomonomers are synthesized by a regioselective, microwave‐assisted approach starting from lactose. The resulting methacrylamide derivatives are polymerized by RAFT and immobilized on gold surfaces using the trithiocarbonate group of the chain transfer agent. Surface plasmon resonance spectroscopy enables the label free kinetic characterization of Gal‐3 binding to these multivalent glycopolymers. The measurements indicate oligomerization of Gal‐3 upon exposure to multivalent environments and reveal strong specific interaction with the immobilized polymers.

Interactions between glycans and proteins have tremendous impact in biomolecular interactions. They are important for cell&ndash, cell interactions, proliferation and much more. Here, we emphasize the glycan-mediated interactions between pathogens and host cells. Pseudomonas aeruginosa, responsible for a huge number of nosocomial infections, is especially the focus when it comes to glycan-derivatives as pathoblockers. We present a microwave assisted protecting group free synthesis of glycomonomers based on lactose, melibiose and fucose. The monomers were polymerized in a precipitation polymerization in the presence of NiPAm to form crosslinked glyco-nanogels. The influence of reaction parameters like crosslinker type or stabilizer amount was investigated. The gels were characterized in lectin binding studies using model lectins and showed size and composition-dependent inhibition of lectin binding. Due to multivalent presentation of glycans in the gel, the inhibition was clearly stronger than with unmodified saccharides, which was compared after determination of the glycan loading. First studies with Pseudomonas aeruginosa revealed a surprising influence on the secretion of virulence factors. Functional glycogels may be in the future potent alternatives or adjuvants for antibiotic treatment of infections based on glycan interactions between host and pathogen.