Parainfluenza Virus 5F Protein
By:
Andrew Braith, Andrew Hipp, Rob Hlavacek, and Ben Krage
Java version
HTML 5 version (does not require Java; downloads and moves
slowly)
I. Introduction
Parainfluenza 5F protein catalyzes the entry of the
viral into
the cell. The F protein undergoes refolding during this
process, which leads to differing conformations when it is
in the pre- and post- transitional states. The parainfluenza
virus is similar to other paramyxovirides, (enveloped
viruses) which include: mumps, measles, sendai, Newcastle,
and the human respiratory sincytial virus. The parainfluenza
5F protein consists of a globular head attached to a
trimeric coiled-coil stalk formed by the C-terminal of the
HRB region. This exact form of the
virus shown in this tutorial is that of the pre-conformational state
in which the stalk sits above the viral membrane. The
pdb file shown does not contain the membrane domain
For more information see
Biochemistry Online: Chapter 5C -
Model Binding Systems
II. General Structure
Wireframe
Cartoon
Cartoon displays the cartoon
configuration of three subunits.
Cartoon
Cartoon displays the specific
secondary structures gold being the beta sheet and pink being the
alpha helix.
Subunit
F-GCNt (Fusion Peptide)
Fusion Peptide: the peptide is sandwiched between the DIII of
its own subunit and the DII of another subunit.
Domain I
Domain II
Domain I and II: during the conformational change domains I and
II reposition as rigid molecules. At the C-terminus of domain II,
an extended linker to HRB, wraps around the trimer to where the
stalk begins.
Domain III
Domain III: this domain acts as a scaffold for the folding
of HRA and subsequently preventing it from forming a helix in the
post-conformational state.
Backbone
Hydrogen Bonds as the Head engages the HRB Stalk
The residues S443 and D448 of
each subunit make hydrogen bonds to the D445 residue of the same
subunit and the S342 of the neighboring subunit.
Spacefill: Subunits
The protein contains three
separate subunits each of which contains three distinct domains.
Solvent accessible surface: dots
Disulfide Bonds
Disulfide Bonds
The bonds are indicated by the yellow lines. The wireframe structures indicate the location of cystine residues.
The next surface displays are solid and require calculations with some time delays
solvent excluded molecular surface (solid 1.4 A) - surface at contact with sphere (molecular)
Map of electrostatic potential
Character: the electron density for the HRB linker is
weaker as compared to the HRB stalk, suggesting that the region has
a greater degree of flexibility. The red
indicates a larger negative charge density while the more blue, the
more positive charge density.
Works Cited:
Hsien-Sheng Yin, Xiaolin Wen, Reay G. Paterson,
Robert A. Lamb, and Theodore S. Jardetzy. "Structure of the
parainfluenza virus 5 F protein in its metastable, prefusion
conformation." Nature. Volume 439, January 2006,
(38-44).