Motion in Tryptophan Synthase [trpsyn]

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Classification Known Domain Motion, Hinge Mechanism [D-h-2]

Structures 1TTP Conformation 2 [ PartsList ] 1TTQ w/ KConformation 3 [ PartsList ] 1UBS w/ lys87 mut.Conformation 4 [ PartsList ] 1WSY Conformation 1 [ PartsList ]

Description Rhee et al. (1997) provide insight into conformational changes that occur upon formation of complexes with product or substrate. Importantly, their two structures having ligands at the active sites of both alpha- and beta-subunits reveal the ordering of the alpha-subunit loop 6 (residues 179-187). The closure of Loop 6 both isolates the active site of the alpha-subunit from the surrounding solvent and results in interaction between alpha-Thr183 and the catalytic residue alpha-Asp60. Other conformational differences between these two mutant structures and the wild type structure include a rigid-body rotation of the alpha-subunit of approximately 5 degrees relative to the beta-subunit and large movements of part of the beta-subunit (residues 93-189) toward the rest of the beta-subunit. Significantly smaller differences are observed in the beta-K87T-Ser structure.

Particular values describing motion Creation Date = 19971130 Modification Date = 19971212 Maximum Rotation (degrees) = 5 ((from abs.)) = x (Traditional x-ray)

References Rhee S, Parris KD, Hyde CC, Ahmed SA, Miles EW, Davies DR (1997). Crystal structures of a mutant (betaK87T) tryptophan synthase alpha2beta2 complex with ligands bound to the active sites of the alpha- and beta-subunits reveal ligand-induced conformational changes. Biochemistry 36(25):7664-7680. [Medline info for 97352620]

GO terms associated with structures Molecular function catalytic activity, tryptophan synthase activity Biological process metabolism, tryptophan metabolism

Morphs

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Best representative Morph Morph name Structure #1 Structure #2 Residues [ ] [ ]

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Copyright 1995-2005 M. Gerstein, W. Krebs, S. Flores, N. Echols, and others
Email: Mark.Gerstein _at_ yale.edu