Date: Tue, 14 Jan 1997 10:50:32 -0800 (PST)
From: Deb McMillen <mcmillen@morel.uoregon.edu>
Subject: Re: papain digests
In-Reply-To: <Pine.SGI.3.91.970113102132.24946A-100000@morel.uoregon.edu>
To: Recipients of ABRF List <abrf@aecom.yu.edu>
Hello, This is Deb again.
Well, communication is still the weak link when working with a large
group of researchers in a Core Facility.
After going over their protocol in more detail--and, then, what they
actually did, we discovered that the digests were done at 25
deg C--so, yesterday afternoon she repeated the digests at 37 deg C--and got
much great digestion of the protein in 15 minutes (more like what I'd
expect)! So that is solved.
I'm still interested, since the question is out there, in "harsh"
conditions that papain can tolerate.
Thanks,
Deb McMillen
On Mon, 13 Jan 1997, Deb McMillen wrote:
> Hello all,
> We are using papain to chew up a protein. We unfold the protein at 90
> deg C and do the digest at 37 deg C. The protein apparently refolds by
> this temperature and is resistant to total cleavage by the papain. I
> would like to know the "harshest" conditions that have been used to do
> papain digests (i.e., how hardy is this enzyme?) How high of a
> temperature will it tolerate (we are working at pH 6-7), is it active in
> 30% acetonitrile (to help unfold the target protein), will it work in the
> presence of detergents?
>
> Thanks for your help,
> Deb McMillen
> Institute of MOlecular Biology
> University of Oregon
>