pyroglutamate aminopeptidase
Jacek_Mozdzanowski-1@SBPHRD.com
Thu, 25 Feb 1999 08:28:18 -0500
David,
We routinely use pyroglutamate aminopeptidase from Pyrococcus furiosus
(supplied by Takara). This enzyme withstands almost any conditions. We
tried even 80 deg C. The enzyme was OK but the protein which we wanted to
deblock was not (and precipitaded). If you follow the protocol which we
published in 1998 (Anal.Biochem, 260, 183-187) the deblocking yield in case
of recombinant immunoglobulins is between 80 and 100%. The enzyme from B-M
is not really any worse (and cheaper), but it will not work well in
temperatures exceeding 37 deg C. Deblocking at 4 deg C may work with very
small peptides but with large proteins (such as IgG) the yield is very
poor. All the enzymes show significant deacy in activity with time and
using an enzyme after its expiration date will produce very poor results.
Jacek Mozdzanowski
Analytical Sciences
SmithKline Beecham