Polyoxazolines with a Vicinally Double-Bioactivated Terminus for Biomacromolecular Affinity Assessment.

Interactions between proteins and carbohydrates with larger biomacromolecules, e.g., lectins, are usually examined using self-assembled monolayers on target gold surfaces as a simplified model measuring setup.

Tuning the Product Spectrum of a Glycoside Hydrolase Enzyme by a Combination of Site-Directed Mutagenesis and Tyrosine-Specific Chemical Modification.

Selective chemical modification of proteins plays a pivotal role for the rational design of enzymes with novel and specific functionalities. In this study, a strategic combination of genetic and chemical engineering paves the way for systematic construction of biocatalysts by tuning the product spectrum of a levansucrase from Bacillus megaterium (Bm-LS), which typically produces small levan-like oligosaccharides. The implementation of site-directed mutagenesis followed by a tyrosine-specific modification enabled control of the product synthesis: depending on the position, the modification provoked either enrichment of short oligosaccharides (up to 800 % in some cases) or triggered the formation of high molecular weight polymer.

Metabolic Glycoengineering of Cell-Derived Matrices and Cell Surfaces: A Combination of Key Principles and Step-by-Step Procedures.

Metabolic glycoengineering allows insertion of non-natural monosaccharides into glycan structures during biosynthesis thereby enabling extracellular matrices (ECMs), cell surfaces, or tissues for decoration with functional cues with ultimate spatial control while deploying aqueous and toxicologically benign coupling chemistries. In this work, we discuss relevant methods in the design of metabolic glycoengineered systems, ranging from synthetic procedures to decoration of cell surfaces and ECM components by bioorthogonal chemistries for widespread biomedical applications. As representative example, we chose a tetra-acetylated azide-bearing monosaccharide as model compound to be metabolically incorporated into glycans of the glycocalyx and ECM components generated by NIH 3T3 cells.

Exploring the Structural Space of the Galectin-1-Ligand Interaction.

Galectin-1 is a tumor-associated protein recognizing the Galβ1-4GlcNAc motif of cell-surface glycoconjugates. Herein, we report the stepwise expansion of a multifunctional natural scaffold based on N-acetyllactosamine (LacNAc). We obtained a LacNAc mimetic equipped with an alkynyl function on the 3'-hydroxy group of the disaccharide facing towards a binding pocket adjacent to the carbohydrate-recognition domain.