Exploring membrane protein folding through protein design, bioinformatics, and molecular biology.
We study how outer membrane proteins fold for the purpose of developing cancer therapeutics, novel vaccines, and methods of environmental remediation.
Our lab is cross-disciplinary, bringing together computational biology, protein design, and molecular biology approaches. We assess the structural bioinformatics of OMPs and apply the results to de novo OMP protein design and to native OMP manipulation.
OMPs are a ripe target for cancer therapeutics. Mitochondria have recently become a focus of cancer therapies due to the fact that mitochondrial outer membrane permeabilization leads to apoptosis or necrosis. We explore mitochondrial membrane permeabilization through manipulation of the OMP pores that already exist in the mitochondrial outer membrane. This may have pharmaceutical consequences because tumorigenic mitochondrial membranes can be selectively targeted in themselves as they have been shown to accumulate lipophilic cations.
Beyond this mechanistic understanding, knowledge of the relationship between OMP chemistry and structure will allow new OMPs to be designed for use in vaccines and will facilitate manipulation of native bacterial OMPs for custom tailored drug delivery systems that could shorten bacterial infections. Outer membrane proteins have been used for the development of vaccines in three distinct ways: as antigens, as adjuvants and as fasteners to conjugate soluble antigens to outer membrane vesicles. Finally, because OMPs are the bacterial import machinery, drugs could be designed in such a way to manipulate OMPs such that those drugs can facilitate their own import into bacteria.
Finally, OMPs also hold great promise for environmental applications. OMPs combine topical accessibility with pore function and/or catalytic function. This combination allows novel OMPs to lead to engineered bacteria that would utilize alternative carbon sources. Designed OMPs could allow bacteria to attach to and degrade unwanted materials. In an environmental application, designed membrane proteins could assist with landfill minimization by allowing bacteria to use polyethylene plastics as a carbon source. Additionally, soil bacteria OMPs could be designed to degrade TNT enabling the deactivation of landmines. By determining many fundamental aspects of how nature forms OMPs we aim to demonstrate how scientists can manipulate these proteins.
- J.S.G. Slusky* and R.L. Dunbrack. “Charge asymmetry in proteins of the outer membrane.” Bioinformatics 29 (2013). *corresponding author [Bioinformatics]
- S. Seppälä, J.S. Slusky, P. Lloris-Garcerá, M. Rapp, G.von Heijne. “Control of membrane protein topology by a single C-terminal residue.” Science 328, (2010). [Science]
- H. Yin*, J.S. Slusky*, B.W. Berger, R.S. Walters, G. Vilaire, R.I. Litvinov, J. D. Lear, G.A. Caputo, J.S. Bennett, W.F. DeGrado. “Computational Design of Peptides that Target Transmembrane Helices” Science 315, (2007).*co-first authors [Science]