%0 Journal Article %A Bello, Sarah %A Rudra, Bashudev %A Gupta, Radhey S. %T Phylogenomic and comparative genomic analyses of Leuconostocaceae species: identification of molecular signatures specific for the genera Leuconostoc, Fructobacillus and Oenococcus and proposal for a novel genus Periweissella gen. nov. %D 2022 %J International Journal of Systematic and Evolutionary Microbiology, %V 72 %N 3 %@ 1466-5034 %C 005284 %R https://doi.org/10.1099/ijsem.0.005284 %K phylogenomic and comparative genomic analyses %K molecular signatures specific for Leuconostoc %K conserved signature indels (CSIs) %K description of the genus Periweissella %K Fructobacillus, Oenococcus and Weissella %I Microbiology Society, %X The genera   Convivina  ,   Fructobacillus  ,   Leuconostoc  ,   Oenococcus   and   Weissella  , which formed the family   Leuconostocaceae  , have recently been merged within the family   Lactobacillaceae  . Using genome sequences for 47 of the 52 named species from these genera, we report here comprehensive phylogenomic and comparative analyses on protein sequences from these species using multiple approaches. In a phylogenomic tree based on concatenated sequences of 498 core proteins from these five genera, and in a 16S rRNA gene tree, members of the genera   Fructobacillus  ,   Leuconostoc   and   Oenococcus   formed distinct strongly supported clades. In contrast,   Weissella   species grouped into two distinct unrelated clades designated as the ‘  Weissella   main clade’ and ‘  Weissella   clade 2’. The presence of these clades is also seen in a matrix of pairwise average amino acid identity based on core protein sequences. In parallel, comparative genomic studies on protein sequences from   Leuconostocaceae   genomes have identified 46 conserved signature indels (CSIs) in diverse proteins that are unique characteristics of the different observed species clades. Of these identified CSIs, five, five and 13 CSIs are uniquely present in members of the genera   Fructobacillus  ,   Leuconostoc   and   Oenococcus  , respectively. We also report here six and five CSIs that are exclusively present in the species from the   Weissella   main clade and   Weissella   clade 2, respectively, providing independent evidence supporting their distinctness from each other. The remaining 12 identified CSIs are commonly shared by some or all of the species from the genera   Convivina  ,   Fructobacillus   and   Leuconostoc  , clarifying their interrelationships. The identified CSIs provide novel and reliable means for the identification/circumscription of members of the genera   Fructobacillus  ,   Leuconostoc   and   Oenococcus   as well as the two   Weissella   species clades in molecular terms. Based on the strong phylogenetic and molecular evidence presented here, we propose that the genus   Weissella   be limited to only the species from the   Weissell  a main clade, whereas the species forming   Weissella   clade 2 should be transferred to a new genus Periweissella gen. nov. %U https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/ijsem.0.005284