2dwp
From Proteopedia
| Line 4: | Line 4: | ||
==Overview== | ==Overview== | ||
| - | To understand the molecular basis of a phosphoryl transfer reaction | + | To understand the molecular basis of a phosphoryl transfer reaction catalyzed by the 6-phosphofructo-2-kinase domain of the hypoxia-inducible bifunctional enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB3), the crystal structures of PFKFB3AMPPCPfructose-6-phosphate and PFKFB3ADPphosphoenolpyruvate complexes were determined to 2.7 A and 2.25 A resolution, respectively. Kinetic studies on the wild-type and site-directed mutant proteins were carried out to confirm the structural observations. The experimentally varied liganding states in the active pocket cause no significant conformational changes. In the pseudo-substrate complex, a strong direct interaction between AMPPCP and fructose-6-phosphate (Fru-6-P) is found. By virtue of this direct substrate-substrate interaction, Fru-6-P is aligned with AMPPCP in an orientation and proximity most suitable for a direct transfer of the gamma-phosphate moiety to 2-OH of Fru-6-P. The three key atoms involved in the phosphoryl transfer, the beta,gamma-phosphate bridge oxygen atom, the gamma-phosphorus atom, and the 2-OH group are positioned in a single line, suggesting a direct phosphoryl transfer without formation of a phosphoenzyme intermediate. In addition, the distance between 2-OH and gamma-phosphorus allows the gamma-phosphate oxygen atoms to serve as a general base catalyst to induce an "associative" phosphoryl transfer mechanism. The site-directed mutant study and inhibition kinetics suggest that this reaction will be catalyzed most efficiently by the protein when the substrates bind to the active pocket in an ordered manner in which ATP binds first. |
==About this Structure== | ==About this Structure== | ||
| Line 10: | Line 10: | ||
==Reference== | ==Reference== | ||
| - | A | + | A direct substrate-substrate interaction found in the kinase domain of the bifunctional enzyme, 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase., Kim SG, Cavalier M, El-Maghrabi MR, Lee YH, J Mol Biol. 2007 Jun 29;370(1):14-26. Epub 2007 Mar 21. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17499765 17499765] |
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Lee, Y | + | [[Category: Lee, Y H.]] |
[[Category: ACP]] | [[Category: ACP]] | ||
[[Category: F6P]] | [[Category: F6P]] | ||
| Line 21: | Line 21: | ||
[[Category: fructose-6-phosphate]] | [[Category: fructose-6-phosphate]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:03:31 2008'' |
Revision as of 15:03, 21 February 2008
|
A pseudo substrate complex of 6-phosphofructo-2-kinase of PFKFB
Overview
To understand the molecular basis of a phosphoryl transfer reaction catalyzed by the 6-phosphofructo-2-kinase domain of the hypoxia-inducible bifunctional enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB3), the crystal structures of PFKFB3AMPPCPfructose-6-phosphate and PFKFB3ADPphosphoenolpyruvate complexes were determined to 2.7 A and 2.25 A resolution, respectively. Kinetic studies on the wild-type and site-directed mutant proteins were carried out to confirm the structural observations. The experimentally varied liganding states in the active pocket cause no significant conformational changes. In the pseudo-substrate complex, a strong direct interaction between AMPPCP and fructose-6-phosphate (Fru-6-P) is found. By virtue of this direct substrate-substrate interaction, Fru-6-P is aligned with AMPPCP in an orientation and proximity most suitable for a direct transfer of the gamma-phosphate moiety to 2-OH of Fru-6-P. The three key atoms involved in the phosphoryl transfer, the beta,gamma-phosphate bridge oxygen atom, the gamma-phosphorus atom, and the 2-OH group are positioned in a single line, suggesting a direct phosphoryl transfer without formation of a phosphoenzyme intermediate. In addition, the distance between 2-OH and gamma-phosphorus allows the gamma-phosphate oxygen atoms to serve as a general base catalyst to induce an "associative" phosphoryl transfer mechanism. The site-directed mutant study and inhibition kinetics suggest that this reaction will be catalyzed most efficiently by the protein when the substrates bind to the active pocket in an ordered manner in which ATP binds first.
About this Structure
2DWP is a Single protein structure of sequence from Homo sapiens with , and as ligands. Full crystallographic information is available from OCA.
Reference
A direct substrate-substrate interaction found in the kinase domain of the bifunctional enzyme, 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase., Kim SG, Cavalier M, El-Maghrabi MR, Lee YH, J Mol Biol. 2007 Jun 29;370(1):14-26. Epub 2007 Mar 21. PMID:17499765
Page seeded by OCA on Thu Feb 21 17:03:31 2008
Categories: Homo sapiens | Single protein | Lee, Y H. | ACP | F6P | MG | A ternary complex | Amppcp | Fructose-6-phosphate
