Structure of an ABC transporter solute‐binding protein specific for the amino sugars glucosamine and galactosamine. Issue 6 (1st June 2016)

• Record Type: Journal Article
• Authors: Yadava, Umesh; Vetting, Matthew W.; Al Obaidi, Nawar; Carter, Michael S.; Gerlt, John A.; Almo, Steven C.
• Is Part Of: Acta crystallographica. Volume 72:Issue 6(2016:Jun.)
• Page Start: 467
• Page End: 472
• Publication Date: 2016-06-01
• Subjects: solute‐binding protein -- differential scanning fluorimetry -- Thermofluor -- Agrobacterium vitis -- Avi_5305 -- Pfam13407; Crystallography -- Periodicals; Crystals -- Periodicals; 548
• DOI: 10.1107/S2053230X16007500
• Languages: English
• ISSNs: 2053-230X

Abstract

Abstract : A solute‐binding protein from Pfam13407 was found to be specific ford ‐glucosamine/d ‐galactosamine by differential scanning fluorimetry and X‐ray crystallography. Abstract : 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 byd ‐glucosamine andd ‐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 tod ‐glucosamine andd ‐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 ford ‐glucosamine/d ‐galactosamine overd ‐glucose/d ‐galactose.