[RASMB] averages from SV

[Joachim Behlke]

Hi Holger and others,

It is not the intension to lengthen the discussion about the average 
sedimentation coefficients but the question to Holger is for what 
purpose the weight average sedimentation coefficients are needed.

As Peter has mentioned the weighted s-values are useful for 
estimating binding constants (e. g. rapid association equilibria).
If you have a system of independend species a good approach is to 
use the s-value determined with DC/DT or DC/DR as starting values 
for a normal fit of the original data. Our program LAMM can do this 
in one run. Up to four independent species can be treated. In our 
last version it is not (more) necessary to make the data points 
equidistant by interpolation (only for absorbance data). That means 
the fit takes place with the unchanged, original data. 
When no resolution is obtained with the DC/DT or DC/DR method,
also not for 60 krpm and long column the exact solution is very 
difficult. The new LAMM version will be send in shortness to the 
RASMB. This version also calculate weighted s-values if the 
DC/DR approach is chosen. The calculation takes place with the 
original, smoothed data trace second moment method.

Regards,

Joachim