A feel for the difference in mobility between lauric (C12) and myristic
(C14) acids was seen in Johnson et al JBC 269 21067 1994. Tryptic digests
were separated on c8 columns and monitored by selected ion plots during
LC/MS. One lauryl peptide eluted at 21.5 min and its myristoyl counterpart
at 24 min. The same peptide with C14:2 (myristoyl with 2 double bonds) ran
with the lauryl peptide. I hope this helps.
Ken
Kenneth A. Walsh
E.W.Davie/ZymoGenetics Chair of Biochemistry
Box # 357350
University of Washington
Seattle WA 98195
walsh@u.washington.edu
Phone 206-543-1768
FAX 206-685-9231
On Fri, 28 Aug 1998, Ken Mitchelhill wrote:
> Colleagues,
>
> I am trying to modify a peptide to serve as an internal standard for an
> HPLC based assay. The requirement is that it elute in the very hydrophobic
> range, say between 50 and 60% acetonitrile from a C8 column, as well as a
> number of other structural features.
>
> I have the base peptide on resin and I have tried a series of N-terminal
> modifications, the most hydrophobic of which is myristoylation (C14) but
> even the myristoyl-form only elutes at just over 40% acetonitrile.
>
> I had thought about just going through the Sigma catalog and ordering a
> series of longer alkyl chlorides but I thought I might ask if anyone has
> experience of making this type of peptide and what the expected increase in
> retention time might be for the addition of more methyl groups to the
> N-terminus?
>
> Regards....Ken
>
> ********************************
>
> Ken I. Mitchelhill
> The John Holt Protein Structure Laboratory
> St. Vincent's Institute of Medical Research
> 41 Victoria Parade
> Fitzroy 3065 Victoria
> AUSTRALIA
>
> Telephone: 61-3-9288 2480
> Facsimile: 61-3-9416 2676
>
> Email: k.mitchelhill@medicine.unimelb.edu.au
>
> Laboratory: http://www.medstv.unimelb.edu.au/WWWDOCS/SVIMRdocs/JHPSL.html
> ABRF: http://www.abrf.org
>
> ***********************************
>
>
>