Structural basis for the broad specificity of a new family of amino-acid racemases

ESPAILLAT, AKBAR; CARRASCO-LOPEZ, CESAR; BERNARDO-GARCIA, NOELIA; PIETROSEMOLLI, NATALIA; OTERO, LISANDRO HORACIO; ALVAREZ, LAURA; DE PEDRO, MIGUEL A.; PAZOS, FLORENCIO; DAVIS, BRIGID M.; WALDOR, MATTHEW K.; HERMOSO, JUAN ANTONIO; CAVA, FELIPE

ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2014 p. 79 - 90

0907-4449

Broad-spectrum amino-acid racemases (Bsrs) enable bacteria to generate noncanonical d-amino acids, the roles of which in microbial physiology, including the modulation of cell-wall structure and the dissolution of biofilms, are just beginning to be appreciated. Here, extensive crystallographic, mutational, biochemical and bioinformatic studies were used to define the molecular features of the racemase BsrV that enable this enzyme to accommodate more diverse substrates than the related PLP-dependent alanine racemases. Conserved residues were identified that distinguish BsrVand a newly defined family of broad-spectrum racemases from alanine racemases, and these residues were found to be key mediators of the multispecificity of BrsV. Finally, the structural analysis of anadditional Bsr that was identified in the bioinformatic analysis confirmed that the distinguishing features of BrsV are conserved among Bsr family members.