From: Borries Demeler <demeler@bioc02.uthscsa.edu>
  To  : rasmb@bbri.harvard.edu
  Date: Wed, 12 Jun 1996 13:01:55 -0500 (CDT)

g(S)t method (fwd)

Forwarded message:
> 
> Hi
> 
> 		I would like to know if anyone have used the "dcdt" method to 
> calculate the apparent sedimetation coefficient distribution for 
> proteins of low s values ( 0.5S to 1.2S or 2S). If so I would like to 
> know how good the analysis obtianed and if any problems were 
> encountered, and of any recent literature of this matter.

You will likely have problems with boundaries not clearing the meniscus
at those very small S values. iIf you run at the highest speed possible in the 
XL-A it may work for the 2S sample. If you know that you have a clean, single 
component sample, you can get excellent results for those kinds of samples
using the finite element solution to the full Lamm equation to fit your 
velocity data. This method includes the boundary conditions (bottom of cell
and meniscus in the actual solution) and thus can model material that hasn't
cleared the meniscus. As an added bonus you will also get the diffusion 
coefficient, molecular weight and fricitional coefficient of the sample.

If you have some data you want me to take a look at, reply by e-mail:

	demeler@bioc02.uthscsa.edu

Regards, -Borries