2esd

From Proteopedia
Jump to navigation Jump to search

Crystal Structure of thioacylenzyme intermediate of an Nadp Dependent Aldehyde DehydrogenaseCrystal Structure of thioacylenzyme intermediate of an Nadp Dependent Aldehyde Dehydrogenase

Structural highlights

2esd is a 4 chain structure with sequence from Streptococcus mutans. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:X-ray diffraction, Resolution 2.55Å
Ligands:,
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

GAPN_STRMU

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

Crystal structures of several members of the nonphosphorylating CoA-independent aldehyde dehydrogenase (ALDH) family have shown that the peculiar binding mode of the cofactor to the Rossmann fold results in a conformational flexibility for the nicotinamide moiety of the cofactor. This has been hypothesized to constitute an essential feature of the catalytic mechanism because the conformation of the cofactor required for the acylation step is not appropriate for the deacylation step. In the present study, the structure of a reaction intermediate of the E268A-glyceraldehyde 3-phosphate dehydrogenase (GAPN) from Streptococcus mutans, obtained by soaking the crystals of the enzyme/NADP complex with the natural substrate, is reported. The substrate is bound covalently in the four monomers and presents the geometric characteristics expected for a thioacylenzyme intermediate. Control experiments assessed that reduction of the coenzyme has occurred within the crystal. The structure reveals that reduction of the cofactor upon acylation leads to an extensive motion of the nicotinamide moiety with a flip of the reduced pyridinium ring away from the active site without significant changes of the protein structure. This event positions the reduced nicotinamide moiety in a pocket that likely constitutes the exit door for NADPH. Arguments are provided that the structure reported here constitutes a reasonable picture of the first thioacylenzyme intermediate characterized thus far in the ALDH family and that the position of the reduced nicotinamide moiety observed in GAPN is the one suitable for the deacylation step within all of the nonphosphorylating CoA-independent ALDH family.

The first crystal structure of a thioacylenzyme intermediate in the ALDH family: new coenzyme conformation and relevance to catalysis.,D'Ambrosio K, Pailot A, Talfournier F, Didierjean C, Benedetti E, Aubry A, Branlant G, Corbier C Biochemistry. 2006 Mar 7;45(9):2978-86. PMID:16503652[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

See Also

References

  1. D'Ambrosio K, Pailot A, Talfournier F, Didierjean C, Benedetti E, Aubry A, Branlant G, Corbier C. The first crystal structure of a thioacylenzyme intermediate in the ALDH family: new coenzyme conformation and relevance to catalysis. Biochemistry. 2006 Mar 7;45(9):2978-86. PMID:16503652 doi:http://dx.doi.org/10.1021/bi0515117

2esd, resolution 2.55Å

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA