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Re: [ccp4bb] normal protein in detergent? |
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CCP4bb navigationCCP4bb <-- 2008 <-- March 2008 <-- 14 March 2008Subject: Re: normal protein in detergent? From: "R {- dot -} M {- dot -} Garavito" garavito {- at -} MSU {- dot -} EDU Date: 2008-03-14 While Joe addressed the possible effects of detergents on the crystallization of proteins, the possible effects (both negative and positive) of detergents on proteins are quite variable. Often there are no general rules except to avoid ionic detergents (from anionic detergents like SDS or sarcoyl or cationic detergents like cetylamine- Br). Also some zwitterionic detergents can become ionic at pH extremes (<5 and >9). As the effects are protein dependent, few general rules have emerged. Sometimes nonionic detergents reduce aggregation or the proteins are stable at high detergent concentrations (>1% w/w). For others, they interfere with activity in the presence of small amounts of detergents. For example, maltose binding protein, which is often used as a fusion protein to aid in purification and to enhance solubility, loses its capacity to bind to amylose columns in the presence of many nonionic detergents. While one might suspect that only glycoside detergents (like octyl glucoside or dodecyl maltoside) might do this, the effect is more general. Hence, when we purify a MBP fusion protein in the presence of nonionic detergents, we often add a His-tag to circumvent this problem, if it arises. The bottom line is that the solution effects of detergents are protein dependent, and few general rules have emerged Cheers, Michael **************************************************************** R. Michael Garavito, Ph.D. Professor of Biochemistry & Molecular Biology 513 Biochemistry Bldg. Michigan State University East Lansing, MI 48824-1319 Office: (517) 355-9724 Lab: (517) 353-9125 FAX: (517) 353-9334 Email: garavito@msu.edu **************************************************************** On Mar 14, 2008, at 9:59 AM, Becker, Joseph W wrote: > Helps sometimes, Start with: > A. McPherson, S. Koszelak, H. Axelrod, J. Day, R. Williams, L. > Robinson, M. McGrath and D. Cascio (1986) An experiment regarding > crystallization of soluble proteins in the presence of beta-octyl > glucoside. J Biol Chem 261:1969-1975. > > Twenty-one soluble proteins, five tRNAs, and three protein-nucleic > acid complexes were studied in a systematic manner with regard to > their crystallization behavior from polyethylene glycol and > ammonium sulfate solutions in the presence of 0 to 1.5% beta-octyl > glucoside. Our observations suggest that this neutral detergent > does influence in a very positive way the growth characteristics of > the macromolecules included in this experiment. In general, more > reproducible and rapid growth was noted with an increased number of > large individual crystals at the expense of microcrystals. In > several cases, new crystal forms were discovered. Selected x-ray > diffraction analyses imply that crystals grown in the presence of > beta-octyl glucoside diffract as well or better than those grown in > its absence. In addition, a screen of two proteins grown in the > presence of 14 different common detergents suggested that a general > detergent effect may be beneficial for the growth of crystals of > biological macromolecules. > > Then check out the detergent screens from Hampton and others > > Joe Becker - Merck Research Labs > > > From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf > Of Melody Lin > Sent: Friday, March 14, 2008 9:40 AM > To: CCP4BB@JISCMAIL.AC.UK > Subject: [ccp4bb] normal protein in detergent? > > Dear all, > > sorry for the off-topic and possibly very naive question- but does > anyone know what happens if normal protein is put in detergent- > containing aqueous solution? how much detergent can a regular > protein tolerate? I was trying to search literature but couldn't > find any... > > Thank you greatly for your attention and inputs. > > Best, > Melody > ---------------------------------------------------------------------- > -------- > 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 (which may be known > outside the United States as Merck Frosst, Merck Sharp & Dohme or MSD > and in Japan, as Banyu - 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. > > ---------------------------------------------------------------------- > -------- > CCP4bb navigationCCP4bb <-- 2008 <-- March 2008 <-- 14 March 2008 |
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