Assessing Squarates as Amine-Reactive Probes.

Probes that covalently label protein targets facilitate the identification of ligand-binding sites. Lysine residues are prevalent in the proteome, making them attractive substrates for covalent probes. However, identifying electrophiles that undergo amine-specific, regioselective reactions with binding site lysine residues is challenging.

Distinguishing Galactoside Isomers with Mass Spectrometry and Gas-Phase Infrared Spectroscopy.

Sequencing glycans is demanding due to their structural diversity. Compared to mammalian glycans, bacterial glycans pose a steeper challenge because they are constructed from a larger pool of monosaccharide building blocks, including pyranose and furanose isomers. Though mammalian glycans incorporate only the pyranose form of galactose (Gal), many pathogens, including and , contain galactofuranose (Gal) residues in their cell envelope.