From Proteopedia
(Difference between revisions)
proteopedia linkproteopedia link
|
|
| Line 1: |
Line 1: |
| - | [[Image:2abb.gif|left|200px]] | + | {{Seed}} |
| | + | [[Image:2abb.png|left|200px]] |
| | | | |
| | <!-- | | <!-- |
| Line 9: |
Line 10: |
| | {{STRUCTURE_2abb| PDB=2abb | SCENE= }} | | {{STRUCTURE_2abb| PDB=2abb | SCENE= }} |
| | | | |
| - | '''Structure of PETN reductase Y186F in complex with cyanide'''
| + | ===Structure of PETN reductase Y186F in complex with cyanide=== |
| | | | |
| | | | |
| - | ==Overview==
| + | <!-- |
| - | The roles of His181, His184 and Tyr186 in PETN reductase have been examined by mutagenesis, spectroscopic and stopped-flow kinetics, and by determination of crystallographic structures for the Y186F PETN reductase and reduced wild-type enzyme-progesterone complex. Residues His181 and His184 are important in the binding of coenzyme, steroids, nitroaromatic ligands and the substrate 2-cyclohexen-1-one. The H181A and H184A enzymes retain activity in reductive and oxidative half-reactions, and thus do not play an essential role in catalysis. Ligand binding and catalysis is not substantially impaired in Y186F PETN reductase, which contrasts with data for the equivalent mutation (Y196F) in Old Yellow Enzyme. The structure of Y186F PETN reductase is identical to wild-type enzyme, with the obvious exception of the mutation. We show in PETN reductase that Tyr186 is not a key proton donor in the reduction of alpha/beta unsaturated carbonyl compounds. The structure of two electron-reduced PETN reductase bound to the inhibitor progesterone mimics the catalytic enzyme-steroid substrate complex and is similar to the structure of the oxidized enzyme-inhibitor complex. The reactive C1-C2 unsaturated bond of the steroid is inappropriately orientated with the flavin N5 atom for hydride transfer. With steroid substrates, the productive conformation is achieved by orientating the steroid through flipping by 180 degrees , consistent with known geometries for hydride transfer in flavoenzymes. Our data highlight mechanistic differences between Old Yellow Enzyme and PETN reductase and indicate that catalysis requires a metastable enzyme-steroid complex and not the most stable complex observed in crystallographic studies.
| + | The line below this paragraph, {{ABSTRACT_PUBMED_16156787}}, adds the Publication Abstract to the page |
| | + | (as it appears on PubMed at http://www.pubmed.gov), where 16156787 is the PubMed ID number. |
| | + | --> |
| | + | {{ABSTRACT_PUBMED_16156787}} |
| | | | |
| | ==About this Structure== | | ==About this Structure== |
| Line 31: |
Line 35: |
| | [[Category: Petn reductase]] | | [[Category: Petn reductase]] |
| | [[Category: Proton transfer]] | | [[Category: Proton transfer]] |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 18:50:50 2008'' | + | |
| | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 29 13:12:32 2008'' |
Revision as of 10:12, 29 July 2008
Template:STRUCTURE 2abb
Structure of PETN reductase Y186F in complex with cyanide
Template:ABSTRACT PUBMED 16156787
About this Structure
2ABB is a Single protein structure of sequence from Enterobacter cloacae. Full crystallographic information is available from OCA.
Reference
Proton transfer in the oxidative half-reaction of pentaerythritol tetranitrate reductase. Structure of the reduced enzyme-progesterone complex and the roles of residues Tyr186, His181, His184., Khan H, Barna T, Bruce NC, Munro AW, Leys D, Scrutton NS, FEBS J. 2005 Sep;272(18):4660-71. PMID:16156787
Page seeded by OCA on Tue Jul 29 13:12:32 2008
