Identification and characterization of RacX, a new broad-specificity amino acid racemase from a novel taxon within the order <i>Flavobacteriales</i>.

ABSTRACT: Amino acid racemases are pivotal for d-amino acid (DAA) biosynthesis with wide-ranging biotechnological applications, yet their industrial deployment is hindered by narrow substrate specificity and instability. Here, we report the discovery of Halocola ammonii gen. nov., sp. nov. DA487^T, a novel taxon within the proposed family Halocolacceae fam. nov. (order Flavobacteriales), isolated from hypersaline sediments. Genomic analysis revealed a robust DAA metabolic network, including a putative broad-specificity racemase RacX. Biochemical characterization demonstrated RacX's exceptional catalytic efficiency (k_cat/K_m = 151.2 s^-1 mM^-1 for l-Lys, k_cat/K_m = 17.8 s^-1

SUBMITTER: Hu L 

PROVIDER: S-EPMC12838360 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature