Don't have an account? Create one
Institution: Log in through your organization’s institutional access. Use this option if you normally select your institution from a list and then sign in with your organization credentials
Federation: Log in through a federation service that connects your organization to multiple systems. Use this option if your organization instructs you to use federated sign-in.
Scientists spy a crown-shaped sulfur ring in mammalian cells
The allotrope cyclo-octasulfur may help buffer lipid oxidation
by

The latest chemistry news, including important research advances, business and policy trends, chemical safety practices, career guidance, and more.
 
Biologists who focus on human cells can tend to think of bacterial metabolism as a bizarre riot, irrelevant to their own fields. But researchers led by Takaaki Akaike at Tohoku University report that an eight-membered sulfur ring, once thought to be a bacterial curiosity, is produced in mammalian cells too (Science 2026, DOI: 10.1126/science.aec5473).
Sulfur is less abundant in biology than elemental heavy hitters like carbon, nitrogen, and oxygen—but where it appears, like in the amino acid cysteine and the metabolite glutathione, it tends to have an outsized role in biochemistry because of its reactivity. The elemental sulfur allotrope, cyclo-octasulfur or S8, is rarer still but has been detected in bacteria and fungi.
S8 is a crown-shaped, redox-neutral ring of elemental sulfur, and Akaike’s team developed a reagent to study it in cells. The reactant is a polyaromatic capsule with a hydrophobic cavity that captures S8 and a charged outer shell that enables mass spectrometry.
With this tool, and later with Raman microscopy, they didn’t find S8 only in bacteria and yeast but also in mouse and human cells.
“I have to say, I would not have thought to look for these [molecules] at all,” Jon Long, whose lab at Stanford University works on identifying new small-molecule metabolites in human biology, writes in an email to C&EN, adding that the detection is convincing.
Based on biochemical experiments, the researchers think glutathione is key to making the S8 in cells. Glutathione dimerizes through a sulfur-sulfur bond, and the researchers think an enzyme better known for nitric oxide synthesis can add additional sulfurs into the linkage between the two glutathione moieties. Eventually, they say, the sulfur chain becomes long enough to form a ring.
Cyclo-octasulfur is hydrophobic and clusters in energy-producing mitochondria and in lipid droplets, organelles that cells use to store fat. The researchers showed some evidence that S8 could act as an antioxidant, helping to prevent lipid oxidation. Long says he’d like to see more data on how this works. He also says the work opens big questions about how the ring fits into sulfur biology. Researchers have become very interested in understanding how cysteine, glutathione, and other sulfur-carrying metabolites contribute to aging and metabolic disease, and this new metabolite may thicken the plot.
Laurel Oldach is a senior editor and life sciences reporter at C&EN.
2/3
FREE ARTICLES LEFT THIS MONTH
Chemistry matters. Join us to get the news you need. Get More
Stay on top of the chemistry world with your editor-curated roundup of C&EN stories
Privacy Policy
C&EN empowers those in and around the global chemical enterprise
Subscribe to C&EN
leftColumns exists: no
The Edge in Chemistry News
Copyright © 2026 American Chemical Society. All Rights Reserved.
Your email has been sent to
Article: