Reactive sulfur species (RSS): persulfides, polysulfides, potential, and problems

Sulfur is a crucial element in biology due to its unique properties and wide range of accessible oxidation states. This reactivity gives rise to the generation of reactive sulfur species (RSS), which have emerged as a diverse class of small molecules and functional groups with important roles in chemical biology and bioinorganic chemistry. In this review, we focus on basic properties of simple RSS, highlight recent insights into the interconnectivity of RSS with reactive nitrogen species, and discuss recent advances in methods for RSS detection and measurement. Finally, we highlight key reactivity considerations that must be taken into account when working with RSS and interpreting the outcomes of labeling methods for RSS and related species.