Genome-Wide Comparative Analysis of Lactiplantibacillus pentosus Isolates Autochthonous to Cucumber Fermentation Reveals Subclades of Divergent Ancestry

Abstract

Lactiplantibacillus pentosus, commonly isolated from commercial cucumber fermentation, is a promising candidate for starter culture formulation due to its ability to achieve complete sugar utilization to an end pH of 3.3. In this study, we conducted a comparative genomic analysis encompassing 24 L. pentosus and 3 Lactiplantibacillus plantarum isolates autochthonous to commercial cucumber fermentation and 47 lactobacillales reference genomes to determine species specificity and provide insights into niche adaptation. Results showed that metrics such as average nucleotide identity score, emulated Rep-PCR-(GTG)5, computed multi-locus sequence typing (MLST), and multiple open reading frame (ORF)-based phylogenetic trees can robustly and consistently distinguish the two closely related species. Phylogenetic trees based on the alignment of 587 common ORFs separated the L. pentosus autochthonous cucumber isolates from olive fermentation isolates into clade A and B, respectively. The L. pentosus autochthonous clade partitions into subclades A.I, A.II, and A.III, suggesting substantial intraspecies diversity in the cucumber fermentation habitat. The hypervariable sequences within CRISPR arrays revealed recent evolutionary history, which aligns with the L. pentosus subclades identified in the phylogenetic trees constructed. While L. plantarum autochthonous to cucumber fermentation only encode for Type II-A CRISPR arrays, autochthonous L. pentosus clade B codes for Type I-E and L. pentosus clade A hosts both types of arrays. L. pentosus 7.8.2, for which phylogeny could not be defined using the varied methods employed, was found to uniquely encode for four distinct Type I-E CRISPR arrays and a Type II-A array. Prophage sequences in varied isolates evidence the presence of adaptive immunity in the candidate starter cultures isolated from vegetable fermentation as observed in dairy counterparts. This study provides insight into the genomic features of industrial Lactiplantibacillus species, the level of species differentiation in a vegetable fermentation habitat, and diversity profile of relevance in the selection of functional starter cultures.

Characterization of Genomic, Physiological, and Probiotic Features of Lactiplantibacillus plantarum JS21 Strain Isolated from Traditional Fermented Jiangshui

“…genetic characteristics to L. pentosus and L. paraplantarum [27]. The ANI a commonly used to determine species membership, confirmed that strain JS21 bel L. plantarum, as the calculated ANI value comparing genomes of L. plantarum, L. p and L. paraplantarum was approximately 88%, significantly lower than the 95% cuto for species membership [51,52]. Collinearity analysis was employed to investigate genome correlation by ide homologous sequences and examining their arrangement consistency among d individuals of the same species [53].…”

“…The studies show that L. plantarum inhabits various environments with similar genetic characteristics to L. pentosus and L. paraplantarum [27]. The ANI analysis, commonly used to determine species membership, confirmed that strain JS21 belongs to L. plantarum, as the calculated ANI value comparing genomes of L. plantarum, L. pentosus, and L. paraplantarum was approximately 88%, significantly lower than the 95% cutoff score for species membership [51,52]. genetic characteristics to L. pentosus and L. paraplantarum [27].…”