Crystal structures of Salmonella enterica FraB deglycase reveal a conformational heterodimer with remarkable structural plasticity at the active site.

ABSTRACT: The fra locus of Salmonella enterica encodes five genes for metabolism of fructose-asparagine, an Amadori product formed by condensation of asparagine with glucose. In the last step of this pathway, the FraB deglycase cleaves 6-phospho-fructose-aspartate into glucose-6-phosphate and aspartate. In homology models, FraB forms a homodimer with two equivalent active sites located at the dimer interface. E214 and H230, two invariant residues essential for catalysis, project into each active site cleft from opposing subunits of the dimer. Here, we have determined six crystal structures of FraB, three of a variant containing an N-terminal His₆ tag and two mutations needed for crystallization (hereafter referred to as WT'), two with additional mutations to active site residues (E214A an

SUBMITTER: Zakharova K 

PROVIDER: S-EPMC12359202 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature