Kinetics of interaction of HIV fusion protein (gp41) with lipid membranes studied by real-time AFM imaging.
One of the most important steps in the process of viral infection is a fusion between cell membrane and virus, which is mediated by the viral envelope glycoprotein. The study of activity of the glycoprotein in the post-fusion state is important for understanding the progression of infection. Here we present a first real-time kinetic study of the activity of gp41 (the viral envelope glycoprotein of human immunodeficiency virus-HIV) and its two mutants in the post-fusion state with nanometer resolution by atomic force microscopy (AFM). Tracking the changes in the phosphatidylcholine (PC) and phosphatidylcholine-phosphatidylserine (PC:PS) membrane integrity over one hour by a set of AFM images revealed differences in the interaction of the three types of protein with zwitterionic and negatively charged membranes. A quantitative analysis of the slow kinetics of hole formation in the negatively charged lipid bilayer is presented. Specifically, analysis of the rate of roughness change for the three types of proteins suggests that they exhibit different types of kinetic behavior.
Bitler
Arkady
A
Department of Chemical Research Support, Israel. arkady.bitler@weizmann.ac.il
Lev
Naama
N
Fridmann-Sirkis
Yael
Y
Blank
Lior
L
Cohen
Sidney R
SR
Shai
Yechiel
Y
D002462:Cell Membrane / Q000378:metabolism; D015700:HIV Envelope Protein gp41 / Q000235:genetics / Q000378:metabolism*; D015497:HIV-1; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007700:Kinetics; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism; D008563:Membrane Lipids / Q000737:chemistry / Q000378:metabolism*; D018625:Microscopy, Atomic Force / Q000379:methods*; D010743:Phospholipids / Q000737:chemistry / Q000378:metabolism
D015700:HIV Envelope Protein gp41; D008051:Lipid Bilayers; D008563:Membrane Lipids; D010743:Phospholipids