MIT Lab Tests Show Peptides Stay Stable in 98% Sulfuric Acid, Boosting Venus Cloud Life Hypothesis MIT researchers recreated Venus-like sulfuric acid clouds and found that peptides can remain stable for weeks, boosting the possibility of life in Venus's atmosphere. MIT researchers have recreated a Venus-like stew of 98% sulfuric acid by weight to test complex signaling molecules called peptides in the lab, and at least three of them passed. The team confirmed that peptides HHQ, HHQ13, and K7 can retain a well-defined and stable structure under these harsh conditions for weeks on end. The work supports the possibility that biochemistry could exist in the clouds of Venus, Earth's nearest planetary neighbor. Venus has a hellish surface where the average temperature could melt lead, but its clouds contain concentrated sulfuric acid that superrotates around the planet. These clouds have long intrigued scientists as a potential habitat for microbial life. The false-color image of Venus, adapted from ultraviolet measurements taken in 2023 by Japan's JAXA Akatsuki spacecraft, depicts its abundant sulfur dioxide cloud content in faint blue. Dark streaks in the cloud cover, seen in images from the European Space Agency's Venus Express, indicate where unknown material, possibly life, has absorbed UV light.Previously, MIT planetary scientist Sara Seager and her collaborators confirmed in the lab that smaller, biologically significant molecules, including lipids, amino acids, and nucleic acids like those found in DNA, could withstand similarly acidic conditions. Seager's team began working with Mei Hong, an MIT chemist, to rerun these tests against peptides due to Hong's expertise in advanced nuclear magnetic resonance (NMR) spectroscopy for the study of biological macromolecules.Hong said that if peptides find their way to that cloud layer of concentrated sulfuric acid, they will stay and be stably preserved in that cloud of droplets. The team explained in its new study that NMR spectroscopy is ideally suited for studying peptides in concentrated sulfuric acid, because site-specific measurements are unaffected by the solvent. The new study was published in a peer-reviewed journal.The new study subjected peptides to extreme concentrations of sulfuric acid, 98% by weight. Using NMR spectroscopy, the researchers confirmed that three peptides, HHQ, HHQ13, and K7, remained stable for weeks. In fact, molecules of the acid appeared to act as scaffolding for the creation of so-called omega loop shapes similar to the geometry of some proteins. This is a compelling indicator that promising biochemistry could be wafting around the acid clouds of Venus.Hong suspects that a lack of water, which plays a key role reacting with sulfuric acid to dissolve peptides, most likely explains these compounds' stability and fascinating 3D shapes under Venus-like conditions. She stated that without water, an acid considered a harsh solvent is not as menacing as one might think. Any life that evolved coasting through Venus's toxic vapors would operate via truly alien biochemical processes.Seager, who has now left MIT for a post at the University of Toronto, said these experiments should be seen as a sign that astrobiologists and other space scientists ought to widen the aperture on what celestial bodies might contain life. She said in a statement that researchers really do not know the full extent of what planet archetypes are out there. They are seeking exoplanets that might be a true Earth twin, but what if they are all Venuses? The findings definitely open up a whole range of possibilities.The study provides evidence that peptides, which can serve as building blocks for proteins, do form in space, with one example present inside the ancient Murchison meteorite. This further supports the idea that the necessary ingredients for life can be delivered to planets and moons, potentially seeding the early Earth and its neighbors. The team's work adds to the growing body of research suggesting that Venus's clouds could be a habitable environment for microbial life.In related news, NASA scientists studied how five Earth microbes might fare on the Moon, including one that already survives outside the International Space Station. Also, this week, the FDA's Pharmacy Compounding Advisory Committee largely voted yes to allowing several peptides to be produced by compounding pharmacies. These developments highlight the growing interest in peptides and their potential roles in both space and medicine.The MIT team's findings were published in a recent issue of the journal Astrobiology. The research was supported by grants from NASA and the Simons Foundation. The researchers plan to continue studying other biomolecules under Venus-like conditions to further assess the habitability of Venus's clouds.