Weissella paramesenteroides UFTM 2.6.1: probiotic potential and biotechnological applications

Abstract

Lactic Acid Bacteria (LAB) constitute a diverse group of Gram-positive bacteria known for their production of lactic acid during carbohydrate fermentation. Among them, Weissella species have emerged as notable candidates for applications in the food and pharmaceutical industries due to their probiotic, biotechnological, and bacteriocinogenic potential. This study presents a comprehensive probiogenomic analysis of Weissella paramesenteroides UFTM 2.6.1 isolated from unpasteurized cow's milk from the Triângulo Mineiro region, exploring its probiotic potential through in vitro and in silico analyses and investigating biotechnological prospects. Taxonomic characterization confirmed the identity of W. paramesenteroides, revealing a genome with 1,926 protein-coding genes primarily linked to cell metabolism, information storage and processing, and cellular processes and signaling. The genome also harbors over 100 genes associated with probiotic traits, such as stress response, gastrointestinal persistence, and biosynthesis of vitamins. In silico analysis identified bacteriocin-related genes, including pediocin, and confirmed in vitro antimicrobial activity of W. paramesenteroides UFTM 2.6.1 against Listeria spp. Genomic analysis identified pLCK4 replicon and four prophage regions (one intact), without CRISPR-Cas systems, Cas proteins, resistance, or virulence genes, suggesting the strain's safety profile. Pan-genome analysis revealed 204 unique genes in W. paramesenteroides UFTM 2.6.1, encompassing metabolism and stress-related functions. These findings highlight its probiotic potential. To investigate relevant literature data on the use of LAB in vaccine strategies, we developed and published an integrative review on recombinant LAB for vaccine development, highlighting their efficacy as potent vectors for mucosal and systemic immunization in animal models. Given this biotechnological potential of LAB, we conducted plasmid design and selection for bacterial integration, resulting in the efficient cloning of the Receptor Binding Domain (RBD) gene of SARS-CoV-2 in Escherichia coli, demonstrating significant synthesis in both supernatant and cell lysate, and recognition by human antibodies. Additionally, we designed a plasmid optimized for LAB, incorporating cassettes for expressing the SARS-CoV-2 RBD gene and IS1223 insertion sequence. This design also features celA as a non-toxic screening marker, avoiding antibiotic resistance concerns. These were preliminary assays that provide insights for future research into LAB, particularly W. paramesenteroides UFTM 2.6.1, requiring further validation to assess its potential as a viable vaccine platform and confirm its probiotic characteristics.