Diverse Sensory Repertoire of Paralogous Chemoreceptors Tlp2, Tlp3, and Tlp4 in Campylobacter jejuni

Microbiology Spectrum, Journal Year: 2022, Volume and Issue: 10(6)

Published: Nov. 14, 2022

Campylobacter jejuni responds to extracellular stimuli via transducer-like chemoreceptors (Tlps). Here, we describe receptor-ligand interactions of a unique paralogue family dCache_1 (double Calcium channels and chemotaxis) chemoreceptors: Tlp2, Tlp3, Tlp4. Phylogenetic analysis revealed that Tlp4 receptors may have arisen through domain duplications, followed by divergent evolutionary drift, with Tlp3 emerging more recently, unexpectedly, responded glycans, as well multiple organic amino acids overlapping specificities. All three Tlps interacted five monosaccharides complex including Lewis's antigens, P fucosyl GM1 ganglioside, indicating potential role in host-pathogen interactions. Analysis chemotactic motility single, double, triple mutants indicated these are likely work together balance responses attractants repellents modulate chemotaxis C. jejuni. Molecular docking experiments, combination saturation transfer difference nuclear magnetic resonance spectroscopy competition surface plasmon analysis, illustrated the ligand-binding possess one major binding pocket two overlapping, but distinct sites able interact ligands. A diverse sensory repertoire could provide ability attractant repellent signals allow for adaptation IMPORTANCE This remarkable perception mechanism allows bacteria sense environmental changes avoid unfavorable conditions or maneuver toward nutrient sources host cells. chemoreceptors, Tlp4, recently. Unlike previous reports ligands interacting proteins, many types chemical compounds, simple sugars such those present on human blood group antigens gangliosides, Diverse

Language: Английский

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The importance of cache domains in α ₂ δ proteins and the basis for their gabapentinoid selectivity

Channels, Journal Year: 2023, Volume and Issue: 17(1)

Published: Feb. 3, 2023

In this hybrid review, we have first collected and reviewed available information on the structure function of enigmatic cache domains in α2δ proteins. These are organized into two double (dCache_1) domains, they present all We also included new data key these with respect to amino acid gabapentinoid binding universal acid–binding pocket, which is α2δ-1 α2δ-2. now identified reason why α2δ-3 α2δ-4 do not bind drugs or acids bulky side chains. relation this, determined that Tryptophan Phenylalanine prevent gabapentin from inhibiting cell surface trafficking α2δ-1. Together, novel shed further light importance

Language: Английский

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The Repertoire of Solute-Binding Proteins of Model Bacteria Reveals Large Differences in Number, Type, and Ligand Range

Microbiology Spectrum, Journal Year: 2022, Volume and Issue: 10(5)

Published: Sept. 19, 2022

Solute-binding proteins (SBPs) are of central physiological relevance for bacteria. They located in the extracytosolic space, where they present substrates to transporters but also stimulate different types transmembrane receptors coordinating compound uptake with signal transduction. SBPs a superfamily composed recognized by 45 Pfam profiles. The definition SBP profiles bacteria is hampered fact that these recognize sensor domains signaling or cytosolic alternative functions. We report here retrieval from 49 bacterial model strains lifestyles and phylogenetic distributions. Proteins were manually curated, ligands predicted bioinformatically. There very large differences number type between strains, ranging 7 Helicobacter pylori 26695 189 Sinorhizobium meliloti 1021. found represent 0.22 5.13% total protein-encoding genes. abundance was largely determined strain phylogeny, no obvious link lifestyle noted. Most abundant (36%) amino acids peptides, followed those expected bind sugars (18%). To best our knowledge, this first comparative study repertoires. Given importance nutrient signaling, enhances knowledge will permit other strains. IMPORTANCE essential components many transporters, multiple pieces more recent evidence indicate SBP-mediated stimulation general widespread transduction mechanism double function transport remains degree unexplored represents major research need. repertoire examined here, along information on their cognate ligand forms basis close gap knowledge. Furthermore, provides forces have driven evolution specificities differ phylogenetics lifestyle. This article step setting up automatic algorithms large-scale identification proteomes.

Language: Английский

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Selective Electrochemical Determination of L-Cysteine by a Cobalt Carbon Nanotube (CNT)-Modified Glassy Carbon Electrode (GCE)

Analytical Letters, Journal Year: 2024, Volume and Issue: 57(17), P. 2798 - 2812

Published: Jan. 12, 2024

L-Cysteine is a semi-essential and proteinogenic amino acid, with the formula HO2CCH (NH2) CH2SH. L-cysteine mostly found in protein-rich foods. In this study, catalysts consisting of cobalt (Co) supported on carbon nanotubes (CNTs) were prepared using sodium borohydride (NaBH4) reduction method. These characterized by means energy-dispersive x-ray (EDX) scanning electron microscopy (SEM), temperature-programmed (TPR), oxidation (TPO) techniques. Characterization results confirmed successful preparation desired catalyst. After preparing Co/CNT catalysts, highly efficient sensitive electrochemical sensor was developed glassy electrode (GCE) modified catalysts. The behavior bare GCE Co/CNT-modified electrodes investigated cyclic voltammetry (CV), differential pulse (DPV), impedance spectroscopy (EIS) 0.1 M phosphate buffer solution (PBS) + L-cysteine. Electrochemical showed that exhibited high sensitivity selectivity compared to GCE, 0.0046 µA/µM, limit detection 0.2 µM, quantification 0.6 µM. Furthermore, higher values than those reported literature. Further interference studies performed CV EIS investigate interfering species serum environment, such as D-glucose, uric L-tyrosine, L-tryptophan. conclusion, suggest promising catalyst for

Language: Английский

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Structural basis for CaVα2δ-gabapentin binding

Biophysical Journal, Journal Year: 2024, Volume and Issue: 123(3), P. 443a - 443a

Published: Feb. 1, 2024

Language: Английский

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