6IOV

The ligand binding domain of Mlp37 with arginine

Summary for 6IOV

• Entry DOI: 10.2210/pdb6iov/pdb
• Related: 3C8C 5AVE 5AVF
• Descriptor: Methyl-accepting chemotaxis (MCP) signaling domain protein, ARGININE (3 entities in total)
• Functional Keywords: chemoreceptor, ligand complex, mcp-like protein, pas-like domain, signaling protein
• Biological source: Vibrio cholerae
• Total number of polymer chains: 2
• Total formula weight: 56597.00

Authors

Takahashi, Y.,Sumita, K.,Nishiyama, S.,Kawagishi, I.,Imada, K. (deposition date: 2018-10-31, release date: 2019-11-06, Last modification date: 2023-11-22)

Primary citation

Takahashi, Y.,Nishiyama, S.I.,Kawagishi, I.,Imada, K.
Structural basis of the binding affinity of chemoreceptors Mlp24p and Mlp37p for various amino acids.
Biochem.Biophys.Res.Commun., 523:233-238, 2020

PubMed Abstract: Environmental sensing is crucial for bacterial survival and pathogenicity. Bacteria sense environmental chemicals using chemoreceptor proteins, such as Methyl-accepting Chemotaxis Proteins (MCPs). Vibrio cholerae, the etiological agent of cholera, has at least 44 chemoreceptor proteins homologous to MCP-Like Proteins (MLPs). Mlp24 and Mlp37 are dCACHE type chemoreceptors that senses various amino acids. Mlp24 is important for cholera toxin production, whereas Mlp37 is related to biofilm formation. The periplasmic ligand binding regions of Mlp24 and Mlp37 (Mlp24p and Mlp37p, respectively) share similar amino acid sequences, tertiary and quaternary structures, and a common mechanism for the ligand amino acid backbone recognition. However, Mlp37p recognizes various l-amino acids and taurine with similar affinity whereas Mlp24p shows different binding affinities for various l-amino acids and does not bind taurine. Here we solved the crystal structure of Mlp37p in complex with l-arginine and compared it with previously determined structures of Mlp37p, Mlp24p and their ligand complexes. We found that Mlp37p changes the conformation of the loop that forms the upper wall of the ligand binding pocket according to size and shape of the ligand, and thereby show similar affinity for various ligands.

PubMed: 31862138
DOI: 10.1016/j.bbrc.2019.12.055

Experimental method

X-RAY DIFFRACTION (2.351 Å)