Structure determination of a sugar-binding protein from the phytopathogenic bacterium Xanthomonas citri

Author(s)

Javier Medrano, Francisco ; de Souza, Cristiane Santos ; Romero, Antonio ; Balan, Andrea

• Document type: Journal article
• Source: ACTA CRYSTALLOGRAPHICA SECTION F-STRUCTURAL BIOLOGY COMMUNICATIONS; v. 70, p. 8-pg., 2014-05-01.

Abstract

The uptake of maltose and related sugars in Gram-negative bacteria is mediated by an ABC transporter encompassing a periplasmic component (the maltose-binding protein or MalE), a pore-forming membrane protein (MalF and MalG) and a membrane-associated ATPase (MalK). In the present study, the structure determination of the apo form of the putative maltose/trehalose-binding protein (Xac-MalE) from the citrus pathogen Xanthomonas citri in space group P6(5)22 is described. The crystals contained two protein molecules in the asymmetric unit and diffracted to 2.8 angstrom resolution. Xac-MalE conserves the structural and functional features of sugar-binding proteins and a ligand-binding pocket with similar characteristics to eight different orthologues, including the residues for maltose and trehalose interaction. This is the first structure of a sugar-binding protein from a phytopathogenic bacterium, which is highly conserved in all species from the Xanthomonas genus. (AU)