Innovative Sulfur Biology Emerging from Supersulfides

　Welcome to our research area "sulfur biology"!
　During a long history of the earth, sulfur, together with iron and oxygen, made a substantial contribution to biogeological evolution. Sulfur is one of the most abundant chemical elements on this planet and has had important roles in the biosphere. For instance, sulfur present as cysteine thiols in proteins is often involved in many fundamental redox reactions in living organisms. Inorganic sulfur, such as elemental sulfur and sulfide, is a major energy source for a group of chemolithotrophic bacteria. Recent advances in analytical chemistry have assured us that sulfur plays fundamental roles in all living beings including humanity.
　A unique chemical characteristic of sulfur is an ability to catenate by itself. In other words, sulfur is an only element that can form chemical linkage into a linear chain without any aids of other elements. Sulfur catenation has a dual chemical reactivities, both electrophilic and nucleophilic, and confers diversity and plasticity on chemical and physical behaviors of sulfur-containing molecules. Based on these peculiar properties, we designate molecules containing sulfur catenation as "supersulfides", a new entity of biomolecules.
　Supersulfides are not described in current textbooks of biochemistry. This is because we could not detect them. Supersulfides are highly reactive and variable in the length of their sulfur catenation, which are both disadvantages for analytical chemistry. To obtain reproducible analytical results, specimens need to be stable and homogeneous. Consequently, thorough reduction was applied to the specimens, resulting in the eradication of catenated sulfur atoms, and we missed most of the supersulfides.
　I am sure that substantial amount of supersulfides is contained in samples on your bench. To let you realize the existence of supersulfides, our most prioritized goal is to establish and propagate various methods and techniques for detection and quantification of supersulfides. We also aim at renovating current life science by taking supersulfides into account and at utilizing supersulfides for contribution to SDGs. Please join us, and why not share the great excitement with us in our research on sulfur biology.