Glycobiology is the comprehensive biological investigation of carbohydrates. The study of the role and function of complex carbohydrates often requires the attachment of carbohydrates to surfaces, their tagging with fluorophores, or their conversion into natural or non-natural glycoconjugates, such as glycopeptides or glycolipids. Glycobiology and its "omics", glycomics, require easy and robust chemical methods for the construction of these glycoconjugates. This review gives an overview of the rapidly expanding field of chemical reactions that selectively convert unprotected carbohydrates into glycoconjugates through the anomeric position. The discussion is divided in terms of the anomeric bond type of the newly formed glycoconjugates, including O-, N-, S-, and C-glycosides.

Methods for site-selective chemistry on proteins are in high demand for the synthesis of chemically modified biopharmaceuticals, as well as for applications in chemical biology, biosensors and more. Inadvertent N-terminal gluconoylation has been reported during expression of proteins with an N-terminal His tag. Here we report the development of this side-reaction into a general method for highly selective N-terminal acylation of proteins to introduce functional groups. We identify an optimized N-terminal sequence, GHHHn− for the reaction with gluconolactone and 4-methoxyphenyl esters as acylating agents, facilitating the introduction of functionalities in a highly selective and efficient manner. Azides, biotin or a fluorophore are introduced at the N-termini of four unrelated proteins by effective and selective acylation with the 4-methoxyphenyl esters. This Gly-Hisn tag adds the unique capability for highly selective N-terminal chemical acylation of expressed proteins. We anticipate that it can find wide application in chemical biology and for biopharmaceuticals.

Three novel gold nanoparticles containing multiple long, flexible linkers decorated with lactose, β-cyclodextrin, and both simultaneously have been prepared. The interaction of such nanoparticles with β-d-galactose-recognizing lectins peanut agglutinin (PNA) and human galectin-3 (Gal-3) was demonstrated by UV-vis studies. Gal-3 is well-known to be overexpressed in several human tumors and can act as a biorecognizable target. This technique also allowed us to estimate their loading capability toward the anticancer drug methotrexate (MTX). Both results make these glyconanoparticles potential site-specific delivery systems for anticancer drugs.

Peptide-based structures can be designed to yield artificial proteins with specific folding patterns and functions. Template-based assembly of peptide units is one design option, but the use of two orthogonal self-assembly principles, oligonucleotide triple helix and a coiled coil protein domain formation have never been realized for de novo protein design. Here, we show the applicability of peptide–oligonucleotide conjugates for self-assembly of higher-ordered protein-like structures. The resulting nano-assemblies were characterized by ultraviolet-melting, gel electrophoresis, circular dichroism (CD) spectroscopy, small-angle X-ray scattering and transmission electron microscopy. These studies revealed the formation of the desired triple helix and coiled coil domains at low concentrations, while a dimer of trimers was dominating at high concentration. CD spectroscopy showed an extraordinarily high degree of α-helicity for the peptide moieties in the assemblies. The results validate the use of orthogonal self-assembly principles as a paradigm for de novo protein design.