I had the same issue before. PAS should be a decent polymer for modification.
On Thu, Nov 9, 2023 at 7:04 PM sadik sattar <sadikqan0...@gmail.com> wrote: > Hi Careina, > > I hope this email finds you well. I wanted to share my experience with a > similar issue I faced in the past concerning one of my proteins, and I've > attached a picture of my round crystals. > > Despite numerous attempts with various screens and additives, I > consistently encountered these round crystals. Interestingly, PEG3350 as > the precipitant seemed to be a common factor in most of these instances. > The crystals would diffract to approximately 6 or 7A in a home source. > > To have a deeper understanding of the situation, I extensively washed the > crystals with the mother liquid and then ran them on the gel. The results > revealed two distinct bands: one corresponding to the expected size of my > protein and another smaller band. Subsequent Mass-spec confirmed that the > smaller band represented a truncated version of my protein. It seemed that > the protein was being cleaved during the course of crystallization and the > cleaved protein is forming crystals with the intact protein. > > Unfortunately, despite my efforts, I couldn't prevent the unintended > cleavage of the protein at that time, leading me to abandon the project. I > wish I had a more definitive solution for you. > > Feel free to reach out if you have any questions or if there's anything > else I can assist you with. > > Best regards, > Sadik. > > > On Nov 8, 2023, at 10:00 AM, careinaedgo...@yahoo.com < > 000002531c126adf-dmarc-requ...@jiscmail.ac.uk> wrote: > > Hi all > We have been trying with no success to crystalize a protein. Recently we > got these strange shape "crystals". They are hard and flat but they do not > diffract at all. Any ideas as to what could cause this? > Careina > > ------------------------------ > > To unsubscribe from the CCP4BB list, click the following link: > https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 > <IMG-20231108-WA0007.jpg> > > > > ------------------------------ > > To unsubscribe from the CCP4BB list, click the following link: > https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 > ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/