We categorized the FMOC amino acids by their coupling rates (as judged by
ninhydrin kinetics) and split these into 3 groups:
fast reactors: A,N,D,G,P,S,C
medium reactors: E,Q,L,K,F,Y,M
slow reactors: R,H,T,W,I,V
An equimolar mixture of each was prepared as a group of slow and medium. 2X
equiv. of I and V were prepared with 1X of the slow reactors, as these were
the slowest. For stoichiometry calculations, the total mass of the combined
powders was split into equal portions.
By splitting the resin in thirds and reacting 1/3 with each set, followed by
recombining, an equal distribution of these amino acids are observed by AAA
after combining.
I hope this protocol is clear.
-----Original Message-----
From: Dr G. Bloomberg [mailto:gbloombe@hgmp.mrc.ac.uk]
Sent: Friday, April 16, 1999 7:23 PM
To: Recipients of ABRF List
Subject:
Dear All
I need to make a peptide where one residue has more or less equal amounts
of all of the amino acids. I know that simply mixing equal
proportions of each Fmoc-amino acid will not achieve this due to different
acylation rates. I do remember somewhere, either at a conference or in the
literature that a study has already been made of this and an
appropriate cocktail was devised. Does anyone know of any references
on this ?
Thanks and regards
Graham Bloomberg
Dept. Biochemistry
Medical School
University of Bristol
Bristol BS8 1TD