A solution 17O-NMR approach for observing an oxidized cysteine residue in Cu,Zn-superoxide dismutase

17O NMR Spectroscopy: A Novel Probe for Characterizing Protein Structure and Folding

Oxygen is a key atom that maintains biomolecular structures, regulates various physiological processes, and mediates various biomolecular interactions. Oxygen-17 (¹⁷O), therefore, has been proposed as a useful probe that can provide detailed information about various physicochemical features of proteins. This is attributed to the facts that (1) ¹⁷O is an active isotope for nuclear magnetic resonance (NMR) spectroscopic approaches; (2) NMR spectroscopy is one of the most suitable tools for characterizing the structural and dynamical features of biomolecules under native-like conditions; and (3) oxygen atoms are frequently involved in essential hydrogen bonds for the structural and functional integrity of proteins or related biomolecules. Although ¹⁷O NMR spectroscopic investigations of biomolecules have been considerably hampered due to low natural abundance and the quadruple characteristics of the ¹⁷O nucleus, recent theoretical and technical developments have revolutionized this methodology to be optimally poised as a unique and widely applicable tool for determining protein structure and dynamics. In this review, we recapitulate recent developments in ¹⁷O NMR spectroscopy to characterize protein structure and folding. In addition, we discuss the highly promising advantages of this methodology over other techniques and explain why further technical and experimental advancements are highly desired.

Efficient labeling of organic molecules using 13C elemental carbon: universal access to 13C2-labeled synthetic building blocks, polymers and pharmaceuticals

Synthetic methodology enabled by ¹³C-elemental carbon is reported. Calcium carbide Ca¹³C₂ was applied to introduce a universal ¹³C₂ unit in the synthesis of labeled alkynes, O,S,N-vinyl derivatives, labeled polymers and ¹³C₂-pyridazine drug core.

A selective colorimetric sensing strategy for cysteine based on an indicator-displacement mechanism

Rapid determination of cysteine in aqueous solution is important for the diagnosis and treatment of some diseases.