Phenotypic Characterization and Genomic Mining of Uric Acid Catabolism Genes in Lactiplantibacillus plantarum YC

This study presents the phenotypic characterization and genomic mining of uric acid catabolism genes in <i>Lactiplantibacillus plantarum</i> YC, a novel food-grade lactic acid bacterium isolated from traditional fermented vegetables with potent uric acid-lowering activity. YC is non-hemolytic, catalase- and gelatinase-negative, exhibits strong adhesion and broad antibacterial activity, and degrades 29.22% of uric acid in vitro, along with complete (100%) degradation of inosine and guanosine. Whole-genome sequencing revealed a 3,214,448 bp chromosome encoding 3026 protein-coding genes. Comparative genomics-based functional annotation highlighted abundant CAZy-related genes and antimicrobial factors, including lysozyme and monooxygenase. Crucially, genomic mining identified a complete uric acid degradation gene cluster, comprising <i>pucK</i> (uric acid permease), <i>hpxO</i> (uric acid hydroxylase), eight copies of <i>hiuH</i> (5-hydroxyisourate hydrolase), <i>allB</i> (allantoinase), and purine nucleoside transport/metabolism genes (<i>rihA</i>, <i>rihB</i>, <i>rihC</i>, <i>pbuG</i>). This work provides the first comparative genomic insight into the genetic architecture and distribution of uric acid metabolism in <i>L. plantarum</i>, elucidating YC's dual urate-lowering mechanism and delivering key molecular markers for developing enzyme-based functional foods and microbial therapeutics against hyperuricemia.