Interactions of Truncated Menaquinones in Lipid Monolayers and Bilayers

Author(s):Show less -

Van Cleave, Cameron ^[1] ; Koehn, Jordan T. ^[1] ; Pereira, Caroline Simoes ^[2] ; Haase, Allison A. ^[1] ; Peters, Benjamin J. ^[1] ; Croslow, Seth W. ^[3] ; McLaughlin, Kyle G. ^[3] ; Werst, Katarina R. ^[1] ; Goach, Audra L. ^[3] ; Crick, Dean C. ^{[4, 5]} ; Arantes, Guilherme Menegon ^[2] ; Crans, Debbie C. ^{[1, 5]}

Affiliation

^[1] Colorado State Univ, Dept Chem, Ft Collins, CO 80523 - USA

^[2] Univ Sao Paulo, Inst Quim, Dept Biochem, Av Prof Lineu Prestes 748, BR-05508900 Sao Paulo, SP - Brazil

^[3] Monmouth Coll, Dept Chem, Monmouth, IL 61462 - USA

^[4] Colorado State Univ, Dept Microbiol Immunol & Pathol, Ft Collins, CO 80523 - USA

^[5] Colorado State Univ, Cell & Mol Biol Program, Ft Collins, CO 80523 - USA

• Document type: Journal article
• Source: INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES; v. 22, n. 18 SEP 2021.
• Web of Science Citations: 0

Abstract

Menaquinones (MK) are hydrophobic molecules that consist of a naphthoquinone headgroup and a repeating isoprenyl side chain and are cofactors used in bacterial electron transport systems to generate cellular energy. We have previously demonstrated that the folded conformation of truncated MK homologues, MK-1 and MK-2, in both solution and reverse micelle microemulsions depended on environment. There is little information on how MKs associate with phospholipids in a model membrane system and how MKs affect phospholipid organization. In this manuscript, we used a combination of Langmuir monolayer studies and molecular dynamics (MD) simulations to probe these questions on truncated MK homologues, MK-1 through MK-4 within a model membrane. We observed that truncated MKs reside farther away from the interfacial water than ubiquinones are are located closer to the phospholipid tails. We also observed that phospholipid packing does not change at physiological pressure in the presence of truncated MKs, though a difference in phospholipid packing has been observed in the presence of ubiquinones. We found through MD simulations that for truncated MKs, the folded conformation varied, but MKs location and association with the bilayer remained unchanged at physiological conditions regardless of side chain length. Combined, this manuscript provides fundamental information, both experimental and computational, on the location, association, and conformation of truncated MK homologues in model membrane environments relevant to bacterial energy production. (AU)

• FAPESP's process: 19/21856-7 - Computational molecular bioenergetics
• Grantee: Guilherme Menegon Arantes
• Support Opportunities: Regular Research Grants