Hi js It happened to us as well with a 1:1 protein complex with decent affinity (Kd about 1 uM). The MPD-based condition (quite high % MPD if I recall correctly) would break the complex apart and only one of the two components formed a crystal (effectively allowing crystallisation of a sample with 50% purity). In the end we did not do anything particularly clever. Changed the construct a bit and the complex gave crystals in a different set of conditions.
Best of luck. Roberto On 1 Feb 2019, at 16:42, Jorg Stetefeld <jorg.stetef...@umanitoba.ca<mailto:jorg.stetef...@umanitoba.ca>> wrote: Hi everyone, this is Joerg Stetefeld. I would like to approach the community in a peculiar case of 2-Methyl-2,4-pentanediol (MPD) impacting our crystallisation experiments. We are working on extracellular ligand-receptor complexes, which we characterize in advance to crystallisation attempts very thoroughly (SEC-MALS/AUC/MST/iSCAMS a.o.). It happens frequently that whenever MPD is part of the setup the complexes are disrupted and just one of the molecules forms a single crystals. Solving these structures shows always a very distinct, spiral-like pore assembly of this respective molecule and the other binding partner cannot be detected. Attempts to “find” and characterize the MPD binding site(s) failed. Remarkably, these phenomena can also be detected in solution and EM images are indicating the same behavior. Did anyone experience similar cases and how can this be avoided? Your advise is appreciated. js Jörg Stetefeld, PhD <https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fstetefeldlab.ca%2F&data=01%7C01%7Croberto.steiner%40KCL.AC.UK%7C1d4e98cb759f4cc0e7e508d68865ad77%7C8370cf1416f34c16b83c724071654356%7C0&sdata=T%2FcqtOHNHWVBLsEACV85UPwcsaMC7Oe%2Ff8k3XQbTFFc%3D&reserved=0> <https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fstetefeldlab.ca%2F&data=01%7C01%7Croberto.steiner%40KCL.AC.UK%7C1d4e98cb759f4cc0e7e508d68865ad77%7C8370cf1416f34c16b83c724071654356%7C0&sdata=T%2FcqtOHNHWVBLsEACV85UPwcsaMC7Oe%2Ff8k3XQbTFFc%3D&reserved=0><https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fstetefeldlab.ca%2F&data=01%7C01%7Croberto.steiner%40KCL.AC.UK%7C1d4e98cb759f4cc0e7e508d68865ad77%7C8370cf1416f34c16b83c724071654356%7C0&sdata=T%2FcqtOHNHWVBLsEACV85UPwcsaMC7Oe%2Ff8k3XQbTFFc%3D&reserved=0>https://stetefeldlab.ca/<https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fstetefeldlab.ca%2F&data=01%7C01%7Croberto.steiner%40KCL.AC.UK%7C1d4e98cb759f4cc0e7e508d68865ad77%7C8370cf1416f34c16b83c724071654356%7C0&sdata=T%2FcqtOHNHWVBLsEACV85UPwcsaMC7Oe%2Ff8k3XQbTFFc%3D&reserved=0> ________________________________ ________________________________ To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1<https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.jiscmail.ac.uk%2Fcgi-bin%2Fwebadmin%3FSUBED1%3DCCP4BB%26A%3D1&data=01%7C01%7Croberto.steiner%40KCL.AC.UK%7C1d4e98cb759f4cc0e7e508d68865ad77%7C8370cf1416f34c16b83c724071654356%7C0&sdata=IOuXvUcn1uYdMvUbF%2B%2BtxWWv1rYDi646gIC3Hw%2FvXDg%3D&reserved=0> Roberto A. Steiner Professor of Biomolecular Structure Randall Centre of Cell and Molecular Biophysics Faculty of Life Sciences and Medicine King's College London roberto.stei...@kcl.ac.uk<mailto:roberto.stei...@kcl.ac.uk> Phone 0044 20 78488216 Fax 0044 20 78486435 Room 3.10A New Hunt's House Guy's Campus SE1 1UL London ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1
