Disulfide cross-linked redox-sensitive peptide condensates are efficient cell delivery vehicles of molecular cargo

Authors

• Malay Mondal, University of Southern Mississippi
• Windfield S. Swetman, University of Southern Mississippi
• Shazeed Ul Karim, University of Southern MississippiFollow
• Sabin Shrestha, University of Southern Mississippi
• Ashe M. Davis, University of Southern Mississippi
• Fengwei Bai, University of Southern MississippiFollow
• Faqing Huang, University of Southern MississippiFollow
• Tristan D. Clemons, University of Southern MississippiFollow
• Vijayaraghavan Rangachari, University of Southern Mississippi

Document Type

Article

Publication Date

10-1-2025

School

Biological, Environmental, and Earth Sciences

Abstract

Biomolecular condensates (BCs) are phase-separated viscoelastic hubs within demixed solutions enriched in proteins and nucleic acids. Such condensates, also called membraneless organelles, are increasingly observed in cells and serve as transient hubs for spatial organization and compartmentalization of biomolecules. Along with the transiency of formation and dissolution, their ability to sequester molecules has inspired us to develop BCs as potential vehicles to transport and deliver molecular cargo. We recently reported the design of disulfide bond cross-linked phase-separating peptide (PSP) condensates that spontaneously dissolve in reducing conditions. Based on the premise that the highly reducing cytoplasm could dissolve PSP condensates and release partitioned cargo, here, we demonstrate the ability of PSP condensates to deliver molecular cargo to the cytoplasm of HeLa cells. We show that PSP condensates deliver a variety of cargos that differ in their sizes and chemistries, including small molecules, peptides, GFP (31 kDa), DNA (1.7 kbp), and mRNA. The transfection efficiencies of PSP condensates for delivering DNA and mRNA were also significantly greater than those of a commercial transfection agent. With room to tailor the condensate properties based on cargo and cell types, these results showcase the potential of disulfide-cross-linked PSPs as effective and customizable cellular delivery vehicles, filling a critical demand gap for such delivery systems.

Publication Title

Proceedings of the National Academy of Sciences of the United States of America

Volume

122

Issue

41

Recommended Citation

Mondal, M., Swetman, W., Karim, S., Shrestha, S., Davis, A., Bai, F., Huang, F., Clemons, T., Rangachari, V. (2025). Disulfide cross-linked redox-sensitive peptide condensates are efficient cell delivery vehicles of molecular cargo. Proceedings of the National Academy of Sciences of the United States of America, 122(41).
Available at: https://aquila.usm.edu/fac_pubs/22289