Message-Id: <c=US%a=_%p=NIH%l=ATLAS-970117234947Z-27194@atlas.niaid.nih.gov>
From: Kenneth Parker <KPARKER@atlas.niaid.nih.gov>
Subject: TFMSA modification
Date: Fri, 17 Jan 1997 18:49:47 -0500
To: Recipients of ABRF List <abrf@aecom.yu.edu>
Dear everybody,
I am trying to determine whether TFMSA (trifluoromethanesulfonic
acid) could be useful for deglycosylating proteins for subsequent mass
spectrometry analysis. I found evidence of RP-HPLC -stable when I
tested to see whether lysozyme was modified, that corresponds to a
gain in MW by MALDI of about 7 molecules of TFMSA per lysozyme. Has
anyone heard of covalent bond formation starting from neat, anhydrous
TFMSA upon addition to protein dried onto a tube (following acetone
precipitation)? I am leaving the protein exposed to TFMSA for only 5
min. on ice prior to neutralization (on ice) with aliquots of
triethylamine prior to dilution into reversed phase solvents prior to
separation. This roughly corresponds to treatments described in JBC
265:6854; JBC 267:25494 and JBC 263:19709, except that that I
substituted triethylamine for pyridine. In the above papers, no MS
data were reported.
Any comments would be useful. I plan also to investigate
deglycosylating enzymes according to published protocols.
Thanks,
Ken Parker
kcp@nih.gov