Primary Citation of Related Structures:   1PFK
PubMed Abstract: 
The crystal structure of Escherichia coli phosphofructokinase complexed with its reaction products fructose 1,6-bisphosphate (Fru1,6P) and ADP/Mg2+, and the allosteric activator ADP/Mg2+, has been determined at 2.4 A resolution. The structure was solved by molecular replacement using the known structure of Bacillus stearothermophilus phosphofructokinase, and has been refined to a crystallographic R-factor of 0 ...
The crystal structure of Escherichia coli phosphofructokinase complexed with its reaction products fructose 1,6-bisphosphate (Fru1,6P) and ADP/Mg2+, and the allosteric activator ADP/Mg2+, has been determined at 2.4 A resolution. The structure was solved by molecular replacement using the known structure of Bacillus stearothermophilus phosphofructokinase, and has been refined to a crystallographic R-factor of 0.165 for all data. The crystallization mixture contained the substrate fructose 6-phosphate, but the electron density maps showed clearly the presence of the product fructose 1,6-bisphosphate, presumably formed by the enzyme reaction with contaminating ATP. The crystal consists of tetrameric molecules with subunits in two different conformations despite their chemical identity. The magnesium ion in the "closed" subunit bridges the phosphate groups of the two products. In the "open" subunit, the products are about 1.5 A further apart, with the Mg2+ bound only to ADP. These two conformations probably represent two successive stages along the reaction pathway, in which the closure of the subunit is required to bring the substrates sufficiently close to react. This conformational change within the subunit is distinct from the quaternary structure change seen previously in the inactive T-state conformation. It is probably not involved in the co-operativity or allosteric control of the enzyme, since the co-operative product fructose 1,6-bisphosphate is not moved, nor are the subunit interfaces changed. The structure of the enzyme is similar to that of B. stearothermophilus phosphofructokinase, and confirms the location of the sites for the two reaction products (or substrates), and of the effector site binding the activator ADP/Mg2+. However, this structure gives a clearer picture of the active site, and of the interactions between the enzyme and its reaction products.
Related Citations: 
Crystal Structure of Unliganded Phosphofructokinase from Escherichia Coli Rypniewski, W.R., Evans, P.R. (1989) J Mol Biol 207: 805
Crystallographic Structure of Allosterically Inhibited Phosphofructokinase at 7 Angstroms Resolution Evans, P.R., Farrants, G.W., Lawrence, M.C. (1986) J Mol Biol 191: 713
Nucleotide Sequence and High-Level Expression of the Major Escherichia Coli Phosphofructokinase Hellinga, H.W., Evans, P.R. (1985) Eur J Biochem 149: 363
Phosphofructokinase. Structure and Control Evans, P.R., Farrants, G.W., Hudson, P.J. (1981) Philos Trans R Soc London,ser B 293: 53
Structure and Control of Phosphofructokinase from Bacillus Stearothermophilus Evans, P.R., Hudson, P.J. (1979) Nature 279: 500
The Three-Dimensional Structure of Phosphofructokinase from Bacillus Stearothermophilus Evans, P.R., Hudson, P.J. (1978) Proc Febs Meet 52: 349
Organizational Affiliation: 
Laboratory of Molecular Biology, Cambridge, England.