Hi Francesca, You could try using reductive methylation, this has always lead to a loss of solubility (and protein!) in my experience. Jena bioscience and Hampton research sell kits.
Best regards, Paul.. [EvotecLogoMail] Paul A. McEwan Ph.D. Principal Scientist, Structural Biology +44. (0)1235 838802 +44. (0)1235 863139 (Fax) [email protected]<mailto:[email protected]> www.evotec.com<http://www.evotec.com/> Evotec (UK) Ltd. 114 Innovation Drive Milton Park Abingdon Oxfordshire OX14 4RZ (United Kingdom) From: CCP4 bulletin board [mailto:[email protected]] On Behalf Of David Briggs Sent: 17 February 2015 08:12 To: [email protected] Subject: Re: [ccp4bb] how to reduce protein solubility Hi Francesca, Try some zinc (1mM + ) in your protein buffer? Zinc tends to make a lot of things less soluble in my hands. Dave On Tue, 17 Feb 2015 04:34 Mattiroli,Francesca <[email protected]<mailto:[email protected]>> wrote: Hi all, I am struggling with a protein complex that is too soluble. I have reached about 20 mg/ml but I still observe very little precipitation (clear drops in 90-95% of the tested conditions). The proteins are expressed in insect cells and going to higher concentration is not easily achievable. I have tried different buffer conditions (salt concentration and pH) and I am testing temperatures. I am at a loss with what to try next. Do you think PTMs (phosphorylation, acetylation) might be causing this? Any input on how to decrease solubility? Thank you very much in advance, Francesca Evotec (UK) Ltd is a limited company registered in England and Wales. Registration number:2674265. Registered office: 114 Innovation Drive, Milton Park, Abingdon, Oxfordshire, OX14 4RZ, United Kingdom.
