1TF1

Crystal Structure of the E. coli Glyoxylate Regulatory Protein Ligand Binding Domain

Summary for 1TF1

• Entry DOI: 10.2210/pdb1tf1/pdb
• Related: 1MKM 1T9L 1TD5
• Descriptor: Negative regulator of allantoin and glyoxylate utilization operons (2 entities in total)
• Functional Keywords: midwest center for structural genomics, glcr, ligand binding domain, transcriptional regulator, psi, protein structure initiative, mcsg, transcription
• Biological source: Escherichia coli
• Total number of polymer chains: 4
• Total formula weight: 85866.30

Authors

Walker, J.R.,Skarina, T.,Kudrytska, M.,Joachimiak, A.,Arrowsmith, C.,Edwards, A.,Savchenko, A.,Midwest Center for Structural Genomics (MCSG) (deposition date: 2004-05-26, release date: 2004-08-03, Last modification date: 2023-08-23)

Primary citation

Walker, J.R.,Altamentova, S.,Ezersky, A.,Lorca, G.,Skarina, T.,Kudritska, M.,Ball, L.J.,Bochkarev, A.,Savchenko, A.
Structural and biochemical study of effector molecule recognition by the E.coli glyoxylate and allantoin utilization regulatory protein AllR.
J.Mol.Biol., 358:810-828, 2006

PubMed Abstract: The interaction of Escherichia coli AllR regulator with operator DNA is disrupted by the effector molecule glyoxylate. This is a general, yet uncharacterized regulatory mechanism for the large IclR family of transcriptional regulators to which AllR belongs. The crystal structures of the C-terminal effector-binding domain of AllR regulator and its complex with glyoxylate were determined at 1.7 and 1.8 A, respectively. Residues involved in glyoxylate binding were explored in vitro and in vivo. Altering the residues Cys217, Ser234 and Ser236 resulted in glyoxylate-independent repression by AllR. Sequence analysis revealed low conservation of amino acid residues participating in effector binding among IclR regulators, which reflects potential chemical diversity of effector molecules, recognized by members of this family. Comparing the AllR structure to that of Thermotoga maritima TM0065, the other representative of the IclR family that has been structurally characterized, indicates that both proteins assume similar quaternary structures as a dimer of dimers. Mutations in the tetramerization region, which in AllR involve the Cys135-Cys142 region, resulted in dissociation of AllR tetramer to dimers in vitro and were functionally inactive in vivo. Glyoxylate does not appear to function through the inhibition of tetramerization. Using sedimentation velocity, glyoxylate was shown to conformationally change the AllR tetramer as well as monomer and dimer resulting in altered outline of AllR molecules.

PubMed: 16546208
DOI: 10.1016/j.jmb.2006.02.034

Experimental method

X-RAY DIFFRACTION (1.8 Å)