Related Experiment Videos
Chemotaxis receptor recognition by protein methyltransferase CheR
1Howard 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.
Nature Structural Biology
|June 17, 1998
Summary
Bacterial chemotaxis receptors are methylated by the CheR enzyme. Structural analysis reveals how CheR specifically binds to receptors, detailing the molecular basis for this crucial signaling interaction.
Area of Science:
- Molecular Biology
- Biochemistry
- Structural Biology
Background:
- Signal transduction relies on reversible covalent modifications of receptors.
- Bacterial chemotaxis receptors undergo reversible methylation on glutamate residues.
- Methylation is catalyzed by S-adenosylmethionine-dependent methyltransferase CheR.
Purpose of the Study:
- To elucidate the structural basis of CheR methyltransferase interaction with chemotaxis receptors.
- To understand the specificity of methylation in bacterial chemotaxis signaling.
Main Methods:
- X-ray crystallography was used to determine the structure of the CheR-AdoHcy-pentapeptide complex.
- The structure was resolved to 2.2 Angstrom resolution.
Main Results:
- The crystal structure reveals the complex of Salmonella typhimurium CheR, S-adenosylhomocysteine (AdoHcy), and the Tar receptor pentapeptide.
- The structure elucidates the specific binding interactions between CheR and the receptor C-terminus.
- A distinct receptor binding motif within the CheR methyltransferase domain was identified.
Conclusions:
- The determined structure provides insight into the molecular recognition mechanism between CheR and its receptor targets.
- This understanding is critical for deciphering the regulation of bacterial chemotaxis signal transduction.