View CNA Protein Structure Network Community Output in VMD

Usage

vmd(...)
"vmd"(x, pdb, layout = layout.cna(x, pdb, k=3), col.sphere=NULL, col.lines = "silver", weights = NULL, radius = table(x$communities$membership)/5, alpha = 1, vmdfile = "network.vmd", pdbfile = "network.pdb", full = FALSE, launch = FALSE, exefile=NULL, ...)
"vmd"(x, pdb, out.prefix = "vmd.cnapath", spline = FALSE, colors = c("blue", "red"), launch = FALSE, exefile=NULL, ...)

Arguments

x
A 'cna' or 'cnapath' class object as obtained from functions cna or cnapath.
pdb
A 'pdb' class object such as obtained from ‘read.pdb’ function.
layout
A numeric matrix of Nx3 XYZ coordinate matrix, where N is the number of community spheres to be drawn.
col.sphere
A numeric vector containing the sphere colors.
col.lines
A character object specifying the color of the edges (default 'silver'). Must use VMD colors names.
weights
A numeric vector specifying the edge width. Default is taken from E(x$community.network)$weight.
radius
A numeric vector containing the sphere radii. Default is taken from the number of community members divided by 5.
alpha
A single element numeric vector specifying the VMD alpha transparency parameter. Default is set to 1.
vmdfile
A character element specifying the output VMD scene file name that will be loaded in VMD.
pdbfile
A character element specifying the output pdb file name to be loaded in VMD.
full
Logical, if TRUE the full all-atom network rather than the clustered community network will be drawn. Intra community edges are colored according to the community membership, while inter community edges are thicker and colored black.
launch
Logical. If TRUE, a VMD session will be started with the output of ‘vmd.cna’.
out.prefix
Prefix for the names of output files, ‘vmd.cnapath.vmd’ and ‘vmd.cnapath.pdb’.
spline
Logical, if TRUE all paths are displayed as spline curves.
colors
Character vector or integer scalar, define path colors. If a character vector, passed to colorRamp function to generate the color scales. If an integer, color all paths the same way with VMD color ID equal to the integer.
exefile
file path to the ‘VMD’ program on your system (i.e. how is ‘VMD’ invoked). If NULL, use OS-dependent default path to the program.
...
additional arguments passed to the function colorRamp (in vmd.cnapath).

Description

This function generates a VMD scene file and a PDB file that can be read and rendered by the VMD molecular viewer. Chose ‘color by chain’ to see corresponding regions of structure colored by community along with the community protein structure network.

Details

This function generates a scaled sphere (communities) and stick (edges) representation of the community network along with the corresponding protein structure divided into chains, one chain for each community. The sphere radii are proportional to the number of community members and the edge widths correspond to network edge weights.

Value

Two files are generated as output. A pdb file with the residue chains assigned according to the community and a text file containing The drawing commands for the community representation.

References

Humphrey, W., Dalke, A. and Schulten, K., ``VMD - Visual Molecular Dynamics'' J. Molec. Graphics 1996, 14.1, 33-38.

Examples

# Load the correlation network from MD data attach(hivp) # Read the starting PDB file to determine atom correspondence pdbfile <- system.file("examples/hivp.pdb", package="bio3d") pdb <- read.pdb(pdbfile) # View cna vmd.cna(net, pdb, launch=FALSE) ## within VMD set 'coloring method' to 'Chain' and 'Drawing method' to Tube ##-- From NMA pdb.gdi = read.pdb("1KJY")
Note: Accessing on-line PDB file
pdb.gdi = trim.pdb(pdb.gdi, inds=atom.select(pdb.gdi, chain="A", elety="CA")) modes.gdi = nma(pdb.gdi)
Building Hessian... Done in 0.18 seconds. Diagonalizing Hessian... Done in 1.785 seconds.
cij.gdi = dccm(modes.gdi)
|======================================================================| 100%
net.gdi = cna(cij.gdi, cutoff.cij=0.35) #vmd.cna(net.gdi, pdb.gdi, alpha = 0.7, launch=TRUE) detach(hivp)

Author

Barry Grant