Micropipette manipulation technique for the monitoring of pH-dependent membrane lysis as induced by the fusion peptide of influenza virus.
We have assembled a micropipette aspiration assay to measure membrane destabilization events in which large (20-30 microns diameter) unilamellar vesicles are manipulated and exposed to membrane destabilizing agents. Single events can be seen with a light microscope and are recorded using both a video camera and a photomultiplier tube. We have performed experiments with a wild-type fusion peptide from influenza virus (X31) and found that it induces pH-dependent, stochastic lysis of large unilamellar vesicles. The rate and extent of lysis are both maximum at pH 5; the maximum rate of lysis is 0.018 s-1 at pH 5. An analysis of our data indicates that the lysis is not correlated either to the size of the vesicles or to the tension created in the vesicle membranes by aspiration.
Soltesz
S A
SA
School of Chemical Engineering, Cornell University, Ithaca, New York 14853.
Hammer
D A
DA
D000595:Amino Acid Sequence; D055592:Biophysical Phenomena; D001703:Biophysics; D006863:Hydrogen-Ion Concentration; D008081:Liposomes; D008561:Membrane Fusion / Q000187:drug effects* / Q000502:physiology; D008722:Methods; D008969:Molecular Sequence Data; D009975:Orthomyxoviridae / Q000235:genetics / Q000502:physiology*; D013050:Spectrometry, Fluorescence; D014760:Viral Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology*
D008081:Liposomes; D014760:Viral Fusion Proteins