Comparative Genomic Analysis of Latilactobacillus curvatus: Insights into Adaptive Evolution and Niche-Specific Traits.

Latilactobacillus curvatus is of considerable industrial relevance, especially in the food sector, owing to its extensive distribution, multifunctional capabilities, and beneficial probiotic properties. This study undertook a comprehensive comparative genomic analysis by sequencing and assembling seven novel L. curvatus genomes and subsequently integrating these with publicly 75 genomes from the NCBI database. The results demonstrated that L. curvatus possesses a closed pangenome structure, indicating substantial environmental and genetic adaptability of this species. Phylogenetic analyses of 1,022 core genes revealed that L. curvatus was divided into three distinct clades (A, B1, and B2), with a clear clustering pattern correlated with the isolation sources. Notably, dairy isolates exhibited significantly larger genome sizes and a higher number of CDS but lower GC content. Moreover, dairy isolates had an elevated copy number of the GH35 gene family, which is crucial for lactose and galactose metabolism, thereby enhancing their adaptation to lactose-rich environments. Additionally, bacteriocin-producing gene clusters were identified in 27 isolates, with meat-derived isolates presenting the highest proportion (37.03%) and fecal isolates the lowest (7.41%), reflecting a niche-specific ecological adaptation. This study elucidates the key genomic features and adaptation mechanisms of L. curvatus, offering valuable theoretical insights into harnessing its probiotic potential.