Motility in Species: Genomic and Phenotypic Characterization and Update on Motility in .

The genus and the recently described genus , to which some previously named species have been reclassified as a result of a taxogenomic assessment, includes lactic acid bacteria species with high biotechnological and probiotic potential. Only one species, namely, (.) , whose type strain has been shown to possess probiotic features, has so far been described to be motile. However, the availability of numerous genome sequences of and species prompted the possibility to screen for the presence of the genetic determinants encoding motility in and spp. other than . Herein, we performed a comprehensive genomic analysis to identify motility-related proteins in all and species described so far, and extended the analysis to the recently sequenced spp. Furthermore, we performed motility assays and transmission electron microscopy (TEM) on type strains to confirm the genomic prediction. The homology-based analysis revealed genes coding for motility proteins only in the type strains of , , and genomes. However, only the type strain was positive in the motility assay and displayed run-and-tumble behavior. Many peritrichous and long flagella on bacterial cells were visualized via TEM, as well. As for the , in addition to the species previously described to harbor motility proteins, the genetic determinants of motility were also found in the genomes of the type strains of and . This study, which is one of the first to analyze the genomes of , and the recently sequenced spp. for the presence of genes coding for motility proteins and which assesses the associated motility phenotypes, provides novel results that expand knowledge on these genera and are useful in the further characterization of lactic acid bacteria.