Hi, Yes, it seems to be a peptide. Our construct was around 52 kDa but our structure has a 12 kDa fragment as this protein undergoes self-proteolysis. In fact previous structures have this fragment only without additional peptides. looks like a caught cleaved product. Protein was expressed in bacteria and purified using affinity and gel filtration chromatography.
Thanks Zeya *Zeyaul Islam, PhD* QBRI - Qatar Biomedical Research Institute P.O. Box: 34110 Doha – Qatar Tel: +974 445 48033 On Mon, Jan 6, 2025 at 11:33 AM Tom Peat <t.p...@unsw.edu.au> wrote: > Hello Zeya, > > More information may be needed to give the community a better chance at > this question. How was the protein expressed and purified? This could lead > to some clues as to what the density may be. > Have you considered that it might be a small peptide? > Best regards, tom > ------------------------------ > *From:* CCP4 bulletin board <CCP4BB@JISCMAIL.AC.UK> on behalf of zeyaul > islam <zeya1...@gmail.com> > *Sent:* Monday, January 6, 2025 6:55 PM > *To:* CCP4BB@JISCMAIL.AC.UK <CCP4BB@JISCMAIL.AC.UK> > *Subject:* [ccp4bb] Unidentified Density > > You don't often get email from zeya1...@gmail.com. Learn why this is > important <https://aka.ms/LearnAboutSenderIdentification> > > Dear all > > We have solved the structure of c1 domain of cardiac isoform of myosin > binding protein-c at 2.1 angstrom. We observe a large unidentified > density near the symmetry. Please have a look at the figures. Protein was > purified in 50 mM Tris.HCl pH 8, 150 mM NaCl, 1 mM DTT and the > crystallisation condition has 0.04 M KPO4, 16% PEG8000 and 20% Glycerol. > Any ideas what this could be? > > Data was collected under cryo condition (glycerol as cryoprotectant) at > automated macromolecular crystallography (AMX) /17-ID-1 beamline of > National Synchrotron Light Source II (NSLSII) located at Brookhaven > National Laboratory (BNL). > > I appreciate any help you can provide. > > Thanks > > Zeya > > *Zeyaul Islam, PhD* > > QBRI - Qatar Biomedical Research Institute > > P.O. Box: 34110 > Doha – Qatar > > Tel: +974 445 48033 > > > ------------------------------ > > 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/
