1BC5: Chemotaxis Receptor Recognition by Protein Methyltransferase Cher

Signal transduction processes commonly involve reversible covalent modifications of receptors. Bacterial chemotaxis receptors are reversibly methylated at specific glutamate residues within coiled-coil regions of their cytoplasmic domains. Methylation is catalyzed by an S-adenosylmethionine-dependent protein methyltransferase, CheR, that binds to a specific sequence at the C-termini of some chemotaxis receptors. From this tethering point, CheR methylates neighboring receptor molecules. We report the crystal structure, determined to 2.2 A resolution, of a complex of the Salmonella typhimurium methyltransferase CheR bound to the methylation reaction product, S-adenosylhomocysteine (AdoHcy), and the C-terminal pentapeptide of the aspartate receptor, Tar. The structure indicates the basis for the specificity of interaction between the chemoreceptors and CheR and identifies a specific receptor binding motif incorporated in the CheR methyltransferase domain.
PDB ID: 1BC5Download
MMDB ID: 86697
PDB Deposition Date: 1998/5/5
Updated in MMDB: 2010/12 
Experimental Method:
x-ray diffraction
Resolution: 2.2  Å
Source Organism:
Salmonella enterica subsp. enterica serovar Typhimurium
Similar Structures:
Biological Unit for 1BC5: dimeric; determined by author and by software (PISA)
Molecular Components in 1BC5
Label Count Molecule
Proteins (2 molecules)
Chemotaxis Receptor Methyltransferase
Molecule annotation
Chemotaxis Receptor
Molecule annotation
Chemicals (2 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB