9KUP

Crystal structure of MCP2201LBD

Summary for 9KUP

• Entry DOI: 10.2210/pdb9kup/pdb
• Descriptor: Methyl-accepting chemotaxis sensory transducer, D-MALATE, SULFATE ION, ... (5 entities in total)
• Functional Keywords: complex, hydrolase
• Biological source: Comamonas thiooxydans
• Total number of polymer chains: 2
• Total formula weight: 40077.24

Authors

Cui, R.,Li, D.F. (deposition date: 2024-12-04, release date: 2025-10-22)

Primary citation

Cui, R.,Li, J.,Hong, Y.,Guo, L.,Wang, Y.H.,Bai, Y.F.,Li, D.F.
Insights into Chemoreceptor MCP2201-Sensing D-Malate.
Int J Mol Sci, 26:-, 2025

PubMed Abstract: Bacterial chemoreceptors sense extracellular stimuli and drive bacteria toward a beneficial environment or away from harm. Their ligand-binding domains (LBDs) are highly diverse in terms of sequence and structure, and their ligands cover various chemical molecules that could serve as nitrogen, carbon, and energy sources. The mechanism of how this diverse range of LBDs senses different ligands is essential to signal transduction. Previously, we reported that the chemoreceptor MCP2201 from CNB-1 sensed citrate and L-malate, altered the ligand-free monomer-dimer equilibrium of LBD to citrate-bound monomer (with limited monomer) and L-malate-bound dimer, and triggered positive and negative chemotactic responses. Here, we present our findings, showing that D-malate binds to MCP2201, induces LBD dimerization, and triggers the chemorepellent response exactly as L-malate did. A single site mutation, T105A, can alter the D-malate-bound LBD dimer into a monomer-dimer equilibrium and switch the negative chemotactic response to D-malate to a positive one. Differences in attractant-bound LBD oligomerization, such as citrate-bound wildtype LBD monomer and D-malate-bound T105A dimer, indicated that LBD oligomerization is a consequence of signal transduction instead of a trigger. Our study expands our knowledge of chemoreceptor-sensing ligands and provides insight into the evolution of bacterial chemoreceptors.

PubMed: 40430039
DOI: 10.3390/ijms26104902

Experimental method

X-RAY DIFFRACTION (1.5 Å)