From: Andrew Leech <A.Leech@uea.ac.uk>
  To  : rasmb@alpha.bbri.org
  Date: Thu, 16 Aug 2001 15:13:23 +0100 (BST)

[RASMB] Effect of isotopes (15N, 13C) on v-bar?

Hello everybody,

 To calculate v-bar for a protein that has been isotopically
labelled, can one simply correct the v-bar calculated by SEDNTERP
by the ratio of the labelled/unlabelled masses, e.g.

normal v-bar 0.7138

normal mass 13187.9; 13C15N mass 13916.2

Hence 13C15N v-bar = 0.7138 x ( 13187.9/13916.2 ) = 0.6764

... or have I made some dubious over-simplification here?

Thanks for any advice,

Andrew

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