It looks like there is a 2-fold axis through the middle, but thinking of HIV protease, that might not stop it being a peptide.
Best wishes, Jon Cooper. jon.b.coo...@protonmail.com Sent from Proton Mail Android -------- Original Message -------- On 06/01/2025 10:26, zeyaul islam wrote: > 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 ######################################################################## 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/