Chemotaxis receptor recognition by protein methyltransferase CheR.
Djordjevic, S., Stock, A.M.(1998) Nat Struct Biol 5: 446-450
- PubMed: 9628482
- DOI: https://doi.org/10.1038/nsb0698-446
- Primary Citation of Related Structures:
1BC5 - PubMed Abstract:
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.
Organizational Affiliation:
Howard Hughes Medical Institute, Center for Advanced Biotechnology and Medicine, and Department of Biochemistry, University of Medicine and Dentistry of New Jersey, Piscataway 08854-5638, USA.