Structure of an ABC transporter solute-binding protein specific for the amino sugars glucosamine and galactosamine

The uptake of exogenous solutes by prokaryotes is mediated by transport systems embedded in the plasma membrane. In many cases, a solute-binding protein (SBP) is utilized to bind ligands with high affinity and deliver them to the membrane-bound components responsible for translocation into the cytoplasm. In the present study, Avi_5305, an Agrobacterium vitis SBP belonging to Pfam13407, was screened by differential scanning fluorimetry (DSF) and found to be stabilized by d-glucosamine and d-galactosamine. Avi_5305 is the first protein from Pfam13407 shown to be specific for amino sugars, and co-crystallization resulted in structures of Avi_5305 bound to d-glucosamine and d-galactosamine. Typical of Pfam13407, Avi_5305 consists of two α/β domains linked through a hinge region, with the ligand-binding site located in a cleft between the two domains. Comparisons with Escherichia coli ribose-binding protein suggest that a cation–π interaction with Tyr168 provides the specificity for d-glucosamine/d-galactosamine over d-glucose/d-galactose.
Source: Acta Crystallographica Section F - Category: Biochemistry Authors: Tags: solute-binding protein differential scanning fluorimetry Thermofluor Agrobacterium vitis Avi_5305 Pfam13407 research communications Source Type: research

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Conclusion The impact of sepsis on the gut is manifold, e.g., sepsis mediated alteration of the gut-blood barrier and increase in the intestinal permeability, which may correlate with the phenomena of bacterial translocation and lymphatic activation (“toxic-lymph”). Systemic consequences of sepsis are widespread and concern to the coagulative system, the microbiome as well as enzymes, such as pancreatic proteases, MMPs and IAPs. Nevertheless, the therapeutic approaches for modulating the mucosal immune system are still rarely effective in daily routine. Recent published studies showing that treatment with FMT,...
Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
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Source: Frontiers in Microbiology - Category: Microbiology Source Type: research
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Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
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Source: Frontiers in Microbiology - Category: Microbiology Source Type: research
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Source: Frontiers in cellular and infection microbiology - Category: Microbiology Source Type: research
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Source: Frontiers in Microbiology - Category: Microbiology Source Type: research
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Source: Frontiers in Microbiology - Category: Microbiology Source Type: research
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Source: Journal of Food Science - Category: Food Science Authors: Tags: Food Microbiology & Safety Source Type: research
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Source: EHP Research - Category: Environmental Health Authors: Tags: Research Source Type: research
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Source: Journal of Biological Chemistry - Category: Chemistry Authors: Tags: Molecular Biophysics Source Type: research
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