Intrinsic reaction-cycle time scale of Na+,K+-ATPase manifests itself in the lipid-protein interactions of nonequilibrium membranes

Research output: Contribution to journalJournal articlepeer-review

Interaction between integral membrane proteins and the lipid-bilayer component of biological membranes is expected to mutually infl uence the proteins and the membrane. We present quantitative evidence of a manifestation of the lipid-protein interactions in liposomal membranes, reconstituted with actively pumping Na+,K+-ATPase, in terms of nonequilibrium shape fluctuations that contain a relaxation time, τ, which is robust and independent of the speci fi c fl uctuation modes of the membrane. In the case of pumping Na+-ions, analysis of the flicker-noise temporal correlation spectrum of the liposomes leads to τ ≃ 0.5 s, comparing favorably with an intrinsic reaction-cycle time of about 0.4 s from enzymology.

Original languageEnglish
JournalProceedings of the National Academy of Sciences of the United States of America
Volume109
Issue number45
Pages (from-to)18442-18446
Number of pages5
ISSN0027-8424
DOIs
Publication statusPublished - 2012
Externally publishedYes

    Research areas

  • Membrane dynamics, Sodium pump reconstituted in giant vesicles, Vesicle fluctuation analysis

ID: 230975063