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.
1ebg
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:1ebg.gif|left|200px]] | [[Image:1ebg.gif|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_1ebg", 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_1ebg| PDB=1ebg | SCENE= }} |
| - | + | ||
| - | + | ||
| - | }} | + | |
'''CHELATION OF SER 39 TO MG2+ LATCHES A GATE AT THE ACTIVE SITE OF ENOLASE: STRUCTURE OF THE BIS(MG2+) COMPLEX OF YEAST ENOLASE AND THE INTERMEDIATE ANALOG PHOSPHONOACETOHYDROXAMATE AT 2.1 ANGSTROMS RESOLUTION''' | '''CHELATION OF SER 39 TO MG2+ LATCHES A GATE AT THE ACTIVE SITE OF ENOLASE: STRUCTURE OF THE BIS(MG2+) COMPLEX OF YEAST ENOLASE AND THE INTERMEDIATE ANALOG PHOSPHONOACETOHYDROXAMATE AT 2.1 ANGSTROMS RESOLUTION''' | ||
| Line 29: | Line 26: | ||
[[Category: Reed, G H.]] | [[Category: Reed, G H.]] | ||
[[Category: Wedekind, J E.]] | [[Category: Wedekind, J E.]] | ||
| - | [[Category: | + | [[Category: Carbon-oxygen lyase]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 14:54:19 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 11:54, 2 May 2008
CHELATION OF SER 39 TO MG2+ LATCHES A GATE AT THE ACTIVE SITE OF ENOLASE: STRUCTURE OF THE BIS(MG2+) COMPLEX OF YEAST ENOLASE AND THE INTERMEDIATE ANALOG PHOSPHONOACETOHYDROXAMATE AT 2.1 ANGSTROMS RESOLUTION
Overview
The structure of a new crystal form of enolase from bakers' yeast has been solved to 2.1-A resolution. Crystals were grown from poly(ethylene glycol) and KCl at pH 8.2 in the presence of Mg2+ and a reaction intermediate analog, phosphonoacetohydroxamate (PhAH). Crystals belong to space group C2; have unit cell dimensions a = 123.5 A, b = 73.9 A, and c = 94.8 A with beta = 93.3 degrees; and contain one dimer per asymmetric unit. The structure was solved by molecular replacement from the X-ray coordinates of apoenolase [Stec, B., & Lebioda, L. (1990) J. Mol. Biol. 211, 235-248]. Both essential divalent metal ions are observed to be complexed with the inhibitor. The two Mg2+ ions are 4.05 A apart and are bridged by a mu-oxyl ligand from the carbonyl moiety of PhAH. The "high-affinity" Mg2+ coordinates to the carboxylate side chains of Asp 246, Glu 295, and Asp 320, one water molecule, and the hydroxamate and carbonyl oxygens of PhAH. The second Mg2+ coordinates to a phosphonyl oxygen, two water molecules, and the mu-bridge carbonyl oxygen of PhAH. Coordination schemes with respect to PhAH and water ligands are fully consistent with those of the Mn2+ complexes determined spectroscopically [Poyner, R.R., & Reed, G. H. (1992) Biochemistry 31, 7166-7173]. Remaining ligands for the second Mg2+ are the carbonyl oxygen and gamma-oxygen of Ser 39. Chelation of this Ser residue to Mg2+ effectively "latches" a flexible loop extending from Gly 37 through His 43 and closes off the entrance to the active site. The position of the second Mg2+ in the active site provides new insight into the stereochemistry of substrate binding.
About this Structure
1EBG is a Single protein structure of sequence from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Chelation of serine 39 to Mg2+ latches a gate at the active site of enolase: structure of the bis(Mg2+) complex of yeast enolase and the intermediate analog phosphonoacetohydroxamate at 2.1-A resolution., Wedekind JE, Poyner RR, Reed GH, Rayment I, Biochemistry. 1994 Aug 9;33(31):9333-42. PMID:8049235 Page seeded by OCA on Fri May 2 14:54:19 2008
