6DSP

LsrB from Clostridium saccharobutylicum in complex with AI-2

Summary for 6DSP

• Entry DOI: 10.2210/pdb6dsp/pdb
• Descriptor: Autoinducer 2-binding protein LsrB, (2R,4S)-2-methyl-2,3,3,4-tetrahydroxytetrahydrofuran (3 entities in total)
• Functional Keywords: ai-2 receptor, signaling protein
• Biological source: Clostridium saccharobutylicum DSM 13864
• Total number of polymer chains: 2
• Total formula weight: 75064.62

Authors

Torcato, I.M.,Xavier, K.B.,Miller, S.T. (deposition date: 2018-06-14, release date: 2019-02-06, Last modification date: 2023-10-11)

Primary citation

Torcato, I.M.,Kasal, M.R.,Brito, P.H.,Miller, S.T.,Xavier, K.B.
Identification of novel autoinducer-2 receptors inClostridiareveals plasticity in the binding site of the LsrB receptor family.
J.Biol.Chem., 294:4450-4463, 2019

PubMed Abstract: Autoinducer-2 (AI-2) is unique among quorum-sensing signaling molecules, as it is produced and recognized by a wide variety of bacteria and thus facilitates interspecies communication. To date, two classes of AI-2 receptors have been identified: the LuxP-type, present in the , and the LsrB-type, found in a number of phylogenetically distinct bacterial families. Recently, AI-2 was shown to affect the colonization levels of a variety of bacteria in the microbiome of the mouse gut, including members of the genus , but no AI-2 receptor had been identified in this genus. Here, we identify a noncanonical, functional LsrB-type receptor in This novel LsrB-like receptor is the first one reported with variations in the binding-site amino acid residues that interact with AI-2. The crystal structure of the receptor determined at 1.35 Å resolution revealed that it binds the same form of AI-2 as the other known LsrB-type receptors, and isothermal titration calorimetry (ITC) assays showed that binding of AI-2 occurs at a submicromolar concentration. Using phylogenetic analysis, we inferred that the newly identified noncanonical LsrB receptor shares a common ancestor with known LsrB receptors and that noncanonical receptors are present in bacteria from different phyla. This led us to identify putative AI-2 receptors in bacterial species in which no receptors were known, as in bacteria belonging to the Spirochaetes and Actinobacteria phyla. Thus, this work represents a significant step toward understanding how AI-2-mediated quorum sensing influences bacterial interactions in complex biological niches.

PubMed: 30696769
DOI: 10.1074/jbc.RA118.006938

Experimental method

X-RAY DIFFRACTION (1.37 Å)