On Mon, Feb 14, 2011 at 5:30 AM, Soisson, Stephen M <[log in to unmask]> wrote:

Hi there,

Was recently looking at a structure of an enzyme with AMP-PNP added to the crystallization mix, and all I see is density for ADP.  I was wondering if hydrolysis of AMP-PNP to ADP is relatively common - either as a result of extended time in crystallization or exposure of the resultant crystals to synchrotron radiation? 

I know that there can be up to 10% contamination of ADP in the purchased material, so it could just be that we have selected that form in the crystal, or that there was endogenous ADP bound that failed to substitute.  Just curious if hydrolysis is a common observation.

Thanks in advance-

Steve

Stephen M. Soisson, Ph.D.
Structural Chemistry Site Lead, WP

Merck Research Laboratories
770 Sumneytown Pike, WP14-1101
West Point, PA  19486
Phone:  (215) 652-6185
Fax:    (215) 652-9051
[log in to unmask]

Notice:  This e-mail message, together with any attachments, contains
information of Merck & Co., Inc. (One Merck Drive, Whitehouse Station,
New Jersey, USA 08889), and/or its affiliates Direct contact information
for affiliates is available at 
http://www.merck.com/contact/contacts.html) that may be confidential,
proprietary copyrighted and/or legally privileged. It is intended solely
for the use of the individual or entity named on this message. If you are
not the intended recipient, and have received this message in error,
please notify us immediately by reply e-mail and then delete it from 
your system.