3N1C

Crystal structure of the phosphofructokinase-2 from Escherichia coli in complex with fructose-6-phosphate

Summary for 3N1C

• Entry DOI: 10.2210/pdb3n1c/pdb
• Related: 3CQD
• Descriptor: 6-phosphofructokinase isozyme 2, 6-O-phosphono-beta-D-fructofuranose (3 entities in total)
• Functional Keywords: phosphofructokinases, pfk-2, escherichia coli, glycolysis, transferase
• Biological source: Escherichia coli
• Total number of polymer chains: 4
• Total formula weight: 130988.14

Authors

Pereira, H.M.,Cabrera, R.,Caniuguir, A.,Garratt, R.C.,Babul, J. (deposition date: 2010-05-15, release date: 2010-12-08, Last modification date: 2023-09-06)

Primary citation

Cabrera, R.,Baez, M.,Pereira, H.M.,Caniuguir, A.,Garratt, R.C.,Babul, J.
The Crystal Complex of Phosphofructokinase-2 of Escherichia coli with Fructose-6-phosphate: KINETIC AND STRUCTURAL ANALYSIS OF THE ALLOSTERIC ATP INHIBITION.
J.Biol.Chem., 286:5774-5783, 2011

PubMed Abstract: Substrate inhibition by ATP is a regulatory feature of the phosphofructokinases isoenzymes from Escherichia coli (Pfk-1 and Pfk-2). Under gluconeogenic conditions, the loss of this regulation in Pfk-2 causes substrate cycling of fructose-6-phosphate (fructose-6-P) and futile consumption of ATP delaying growth. In the present work, we have broached the mechanism of ATP-induced inhibition of Pfk-2 from both structural and kinetic perspectives. The crystal structure of Pfk-2 in complex with fructose-6-P is reported to a resolution of 2 Å. The comparison of this structure with the previously reported inhibited form of the enzyme suggests a negative interplay between fructose-6-P binding and allosteric binding of MgATP. Initial velocity experiments show a linear increase of the apparent K(0.5) for fructose-6-P and a decrease in the apparent k(cat) as a function of MgATP concentration. These effects occur simultaneously with the induction of a sigmoidal kinetic behavior (n(H) of approximately 2). Differences and resemblances in the patterns of fructose-6-P binding and the mechanism of inhibition are discussed for Pfk-1 and Pfk-2, as an example of evolutionary convergence, because these enzymes do not share a common ancestor.

PubMed: 21147773
DOI: 10.1074/jbc.M110.163162

Experimental method

X-RAY DIFFRACTION (2 Å)