Hello, this looks like beta-mercaptoethanol adduct through a S-S bond. See [ https://pubmed-ncbi-nlm-nih-gov.insb.bib.cnrs.fr/12421561/ | The crystal structure of the Epstein-Barr virus protease shows rearrangement of the processed C terminus. ] Buisson M, Hernandez JF, Lascoux D, Schoehn G, Forest E, Arlaud G, Seigneurin JM, Ruigrok RW, Burmeister WP. J Mol Biol. 2002 Nov 15;324(1):89-103. doi: 10.1016/s0022-2836(02)01040-9.
Wim De: "Liliana Margent" <[email protected]> À: "CCP4BB" <[email protected]> Envoyé: Lundi 18 Décembre 2023 18:03:46 Objet: [ccp4bb] extra Fo-Fc density in two Cysteines Hi there, We’ve been having an issue in trying to clear regions of Fo-Fc density from a few cysteines during the refinement process. We were wondering if anyone had seen something similar so they could offer some insight on the likely chemistry at hand, and a potential refinement solution. Attached are two images of the observed extra density at two cysteines, 505 and 518. We have modeled acetylated cysteine, s-hydroxycysteine, and s-mercaptocysteine but it does not solve the density. The protein in question is a Protein Tyrosine Phosphatase known as STEP (PTPN5), with data collected to a resolution of 1.79 Å. The crystals were grown in bis-tris pH 6.65, 200mM Li2SO4, ~30% PEG3350. Of note, prior to data collection the crystal was conserved at room temp for long time where it dried, and was subsequently rehydrated with mother liquor. Thank you so much. To unsubscribe from the CCP4BB list, click the following link: [ https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 | https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 ] [image/png:Screenshot 2023-12-16 at 3.36.01 PM.png] -- Wim Burmeister Professor Institut de Biologie Structurale (IBS) CIBB 71 avenue des Martyrs / CS 20192 38044 Grenoble Cedex 9, FRANCE E-mail: [ mailto:[email protected] | [email protected] ] Mobile: +33 (0) 7 50 49 19 91 [ https://www.ibs.fr/en/research/microbiology-infection-and-immunity/viral-replication-machines-group-m-jamin/team-burmeister/ | website ] [ http://www.ibs.fr/research/research-groups/viral-replication-machines-group-m-jamin/team-03/article/poxvirus-replication-machinery-presentation/ ] [ https://showyourstripes.info/s/europe/france/all | https://showyourstripes.info/s/europe/france/all ] ######################################################################## 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/
