Dear Kostas There is a chance your protein is not properly folded by is solubilized by the large MBP tag, and this may be the reason for aggregation.
Bostjan --- Bostjan Kobe NHMRC Research Fellow Professor of Structural Biology School of Chemistry and Molecular Biosciences and Institute for Molecular Bioscience (Division of Chemistry and Structural Biology) and Centre for Infectious Disease Research Cooper Road University of Queensland Brisbane, Queensland 4072 Australia Phone: +61 7 3365 2132 Fax: +61 7 3365 4699 E-mail: b.k...@uq.edu.au URL: http://www.scmb.uq.edu.au/staff/bostjan-kobe Office: Building 76 Room 329 Notice: If you receive this e-mail by mistake, please notify me, and do not make any use of its contents. I do not waive any privilege, confidentiality or copyright associated with it. Unless stated otherwise, this e-mail represents only the views of the Sender and not the views of The University of Queensland. From: Gang Dong <gang.d...@univie.ac.at<mailto:gang.d...@univie.ac.at>> Reply-To: Gang Dong <gang.d...@univie.ac.at<mailto:gang.d...@univie.ac.at>> Date: Wed, 24 Jul 2013 18:53:27 +0200 To: <CCP4BB@JISCMAIL.AC.UK<mailto:CCP4BB@JISCMAIL.AC.UK>> Subject: Re: [ccp4bb] Maltose binding protein as a tag Dear Kostas, MBP by itself is a monomer. In most of our cases using it as a fusion tag, the yield of a target protein increases drastically (i.e. 5 to >20 folds more). However, we have seen in a couple of cases that the target proteins strongly interact with the MBP tag, which causes oligomerization of the fusion protein. To check whether you have encountered a similar issue, you can try to cut the tag off and check whether your protein still sticks to MBP. Good luck, Gang From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf Of Konstantinos Paraskevopoulos Sent: Wednesday, July 24, 2013 3:07 PM To: CCP4BB@JISCMAIL.AC.UK<mailto:CCP4BB@JISCMAIL.AC.UK> Subject: [ccp4bb] Maltose binding protein as a tag Dear all, I would like to ask if someone has experience with maltose binding protein (MBP) as a tag. My protein fused to MBP seems to form oligomers that I find difficult to prevent and I was wondering if mbp behaves similar to gst and may also be prone to dimerisation/oligomerisation Many thanks in advance Kostas Paraskevopoulos Research fellow University of edinburgh
