![]() |
![]()
Motion in Fructose-1,6-biphosphatase [fbp]
[ jump to morphs ]
Classification Known Subunit Motion, Involving Allostery [S-a-2]
Structures 1FBT Conformation 1 [ PartsList ] 1TIP Conformation 1 [ PartsList ]
Description The structure of the neutral form of fructose-1,6-bisphosphatase complexed with AMP (and MG) was determined and shown to have a different quaternary structure than that of the unliganded enzyme. Specifically, two major quaternary conformational changes are observed: (1) A twist of dimer C3-C4 about the molecular 2-fold axis p by roughly 19 degrees relataive to dimer C1-C2, and (2) a translation of approximately 1 A of the AMP domains. The conformational shift between the T and R allosteric forms induced by AMP binding is also observed to induce a large movment of residues in the AMP domain.Superimposition of the two structures show average C-alpha displacements over the entire FBP domain in these complexes of 0.35 A. Glu97, Glu97, and Asp121 shift over 1 A, while C-alpha positions for Asp118 and Glu280 are observed to move 0.5 and 0.3 A, respectively. The largest changes in the R to T transition occur in the interdimeric interface, mainly made up of helices H1, H2, and H3. The dimer C3-C4 undergoes a 19 degree twist, placing the upper H2 helix close to the lower H3 helix in the T form.
Particular values describing motion Maximum Rotation (degrees) = 19 ((from article)) Experimental Methods = x (Traditional x-ray) Creation Date = 19971130 Modification Date = 19971212
References Ke HM, Liang JY, Zhang YP, Lipscomb WN (1991). Conformational transition of fructose-1,6-bisphosphatase: structure comparison between the AMP complex (T form) and the fructose 6-phosphate complex (R form). Biochemistry 30(18):4412-4420. [Medline info for 91214982]
GO terms associated with structures Molecular function catalytic activity, ATP binding Biological process metabolism, fructose 2,6-bisphosphate metabolism
Morphs
[ show all images ]
Best representative Morph Morph name Structure #1 Structure #2 Residues Fructose 1,6-biphosp 1fbt [ A ] 1tip [ A ] 190
![]()
![]()
![]()
Copyright 1995-2005 M. Gerstein, W. Krebs, S. Flores, N. Echols, and others
Email: Mark.Gerstein _at_ yale.edu