Howdie folks:
I'm preparing my annual X-ray diffraction lectures, and am at the
point where one replaces the atomic scattering factor with the
integrated electron density.
It has always bothered me how this is a bit obscure, since it really
lies at the heart of the physical description.
Dear all,
I thank everyone who directed me to coiled coil structures where the alpha
helical chains are related by a crystallographic axis. My question was prompted
by an examination of structures (mainly parallel homodimers) where this is not
the case. In most structures, including 2zta (the c
James Holton wrote:
I think the definition of a "coiled coil" is that the helices are
symmetric (Crick 1953).
This is only true for parallel in register coiled coils.
There are many coiled coils that are antiparallel,
see e.g. the SOCKET database at
http://www.lifesci.sussex.ac.uk/research/woo
I think the definition of a "coiled coil" is that the helices are
symmetric (Crick 1953). That is, every coiled coil is a helical bundle,
but not every helical bundle is a coiled coil. It is a matter of
semantics as to HOW MUCH a coiled coil can deviate from perfect internal
symmetry before i
Dear all,
Is anyone aware of a structure where the individual alpha helical
chains of a coiled coil are related by a crystallographic axis? Or does
anyone know of a coiled coil structure (dimer or higher order
oligomer) that is perfectly symmetric at least in
I am not sure if this is exactly what you are asking about but 1nig in
pdb sounds awfully like what you are describing.
Also take a look at J Struct Funct Genomics.
2004;5(4):231-40 for more detailed description of the structure.
Cheers,
Nukri
Ruslan Sanishvili (Nukri), Ph.D.
GM/CA-C
