The Small Matter of a Red Ox, a Particularly Sensitive Pink Cat, and the Quest for the Yellow Stone of Wisdom

Purpose of Review: The article describes how recent advances in chalcogen Redox Biology shape the future of nutrition, drug design, agriculture, and environmental management. Recent Findings: Since the turn of the Millennium, the biological chemistry of redox active sulfur species has witnessed various significant developments, with cysteine side-chains in proteins and enzymes emerging as centers of redox signaling and control and inspiring new concepts, such as the sulfur redoxome, the sulfenome, and the cellular thiolstat. Since then, it has emerged that redox sensitive cysteine residues are preferred targets of Reactive Sulfur Species (RSS), certain metal ions, and the emerging class of Reactive Selenium Species (RSeS). In addition, the cellular redoxome provides the basis for targeted redox modulation, for instance via nutritional intervention in the sick and elderly; it paves the way for highly selective catalytic sensor/effector agents active against a spectrum of redox-related diseases and lightens up possible avenues leading towards green phyto-protectants, often in cahoots with modern nanotechnology. Whilst the activity of redox-active food ingredients and multifunctional redox-modulating compounds on and in cells is complicated, modern techniques such as redox proteomics and chemogenetic phenotype profiling in combination with fluorescent-based “intracellular diagnostics” can be employed to illuminate certain changes, pathways, and eventually, also mode(s) of action. Summary: Undoubtedly, chalcogen-based redox systems will shape future research and development in nutrition, drug design, cosmetics, green agriculture, and waste management.