This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
2g0f
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:2g0f.gif|left|200px]] | [[Image:2g0f.gif|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_2g0f", creates the "Structure Box" on the page. | |
| - | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
| - | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |
| - | + | or leave the SCENE parameter empty for the default display. | |
| - | + | --> | |
| - | + | {{STRUCTURE_2g0f| PDB=2g0f | SCENE= }} | |
| - | + | ||
| - | + | ||
| - | }} | + | |
'''Crystal Structure of P144A mutant of E.coli CcmG protein''' | '''Crystal Structure of P144A mutant of E.coli CcmG protein''' | ||
| Line 29: | Line 26: | ||
[[Category: Ouyang, N.]] | [[Category: Ouyang, N.]] | ||
[[Category: Xia, Z X.]] | [[Category: Xia, Z X.]] | ||
| - | [[Category: | + | [[Category: Cis-to-trans configuration change]] |
| - | [[Category: | + | [[Category: E coli ccmg]] |
| - | [[Category: | + | [[Category: P144a mutant]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun May 4 04:33:21 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 01:33, 4 May 2008
Crystal Structure of P144A mutant of E.coli CcmG protein
Overview
CcmG, also designated DsbE, functions as a periplasmic protein thiol:disulfide oxidoreductase and is required for cytochrome c maturation. Here we report the crystal structures of Escherichia coli CcmG and its two mutants, P144A and the N-terminal fifty seven-residue deletion mutant, and two additional deletion mutants were studied by circular dichroism. Structural comparison of E. coli CcmG with its deletion mutants reveals that the N-terminal beta-sheet is essential for maintaining the folding topology and consequently maintaining the active-site structure of CcmG. Pro144 and Glu145 are key residues of the fingerprint region of CcmG. Pro144 is in cis-configuration, and it makes van der Waals interactions with the active-site disulfide Cys80-Cys83 and forms a C--H...O hydrogen bond with Thr82, helping stabilize the active-site structure. Glu145 forms a salt-bridge and hydrogen-bond network with other residues of the fingerprint region and with Arg158, further stabilizing the active-site structure. The cis-configuration of Pro144 makes the backbone nitrogen and oxygen of Ala143 exposed to solvent, favorable for interacting with binding partners. The key role of cis-Pro144 is verified by the P144A mutant, which contains trans-Ala144 and displays redox property changes. Structural comparison of E. coli CcmG with the recently reported structure of CcmG in complex with the N-terminal domain of DsbD reveals that Tyr141 undergoes conformational changes upon binding DsbD. A cis-proline located at the N-terminus of the first beta-strand of the betabetaalpha motif of the thioredoxin-like domain is a conserved structural feature of the thioredoxin superfamily.
About this Structure
2G0F is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structures of E. coli CcmG and its mutants reveal key roles of the N-terminal beta-sheet and the fingerprint region., Ouyang N, Gao YG, Hu HY, Xia ZX, Proteins. 2006 Dec 1;65(4):1021-31. PMID:17019698 Page seeded by OCA on Sun May 4 04:33:21 2008
