1b9m
REGULATOR FROM ESCHERICHIA COLIREGULATOR FROM ESCHERICHIA COLI
Structural highlights
FunctionMODE_ECOLI The ModE-Mo complex acts as a repressor of the modABC operon, involved in the transport of molybdate. Upon binding molybdate, the conformation of the protein changes, promoting dimerization of ModE-Mo. The protein dimer is then competent to bind a DNA region, upstream of the modABC operon, which contains an 8-base inverted repeat 5'-TAACGTTA-3' flanked by two CAT boxes. Acts also as an enhancer of the expression of genes coding for molybdoenzymes, both directly and indirectly. ModE also interacts with tungstate. Evolutionary Conservation![]() Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe molybdate-dependent transcriptional regulator (ModE) from Escherichia coli functions as a sensor of molybdate concentration and a regulator for transcription of operons involved in the uptake and utilization of the essential element, molybdenum. We have determined the structure of ModE using multi-wavelength anomalous dispersion. Selenomethionyl and native ModE models are refined to 1. 75 and 2.1 A, respectively and describe the architecture and structural detail of a complete transcriptional regulator. ModE is a homodimer and each subunit comprises N- and C-terminal domains. The N-terminal domain carries a winged helix-turn-helix motif for binding to DNA and is primarily responsible for ModE dimerization. The C-terminal domain contains the molybdate-binding site and residues implicated in binding the oxyanion are identified. This domain is divided into sub-domains a and b which have similar folds, although the organization of secondary structure elements varies. The sub-domain fold is related to the oligomer binding-fold and similar to that of the subunits of several toxins which are involved in extensive protein-protein interactions. This suggests a role for the C-terminal domain in the formation of the ModE-protein-DNA complexes necessary to regulate transcription. Modelling of ModE interacting with DNA suggests that a large distortion of DNA is not necessary for complex formation. The high-resolution crystal structure of the molybdate-dependent transcriptional regulator (ModE) from Escherichia coli: a novel combination of domain folds.,Hall DR, Gourley DG, Leonard GA, Duke EM, Anderson LA, Boxer DH, Hunter WN EMBO J. 1999 Mar 15;18(6):1435-46. PMID:10075916[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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