The human microbiota contributes to maintaining specific physiological equilibria that support the host’s health. When the balance among microorganisms inhabiting a particular body site is disrupted, various diseases may develop. The gut–vaginal axis is one example of the connections between the gut and other organs, where dysbiosis in one microbial community can influence the other. In this context, probiotics may represent a useful strategy to help restore microbial balance within these niches and to limit the excessive proliferation of pathogenic organisms. This study focuses on the genomic and phenotypic characterization of Lactobacillus crispatus P 17631 to evaluate its potential use as a probiotic strain for intestinal and vaginal health. Accordingly, whole-genome analysis was performed to assess the safety and functional properties of Lactobacillus crispatus P 17631 in compliance with EFSA guidelines, confirming the absence of virulence factors and transferable antibiotic resistance genes. Furthermore, a genomic screening approach was employed to identify genes associated with stress tolerance, adhesion capacity, and antimicrobial activity. To validate the probiotic potential predicted from genomic analyses, a series of phenotypic assays were conducted. The strain’s ability to withstand gastrointestinal conditions was evaluated by assessing (i) pH stability, (ii) tolerance to bile salts, and (iii) adhesion capacity to epithelial cells, a key trait for colonization and persistence on host mucosal surfaces. Functional assays further examined the strain’s antimicrobial activity and its ability to inhibit the growth of opportunistic pathogens associated with intestinal or vaginal dysbiosis, including Candida spp. The integration of genomic analyses with in vitro functional assays enabled the generation of a comprehensive characterization of Lactobacillus crispatus P17631. The resulting data support both the safety profile and the probiotic potential of this strain, and provide a foundation for future investigations aimed at assessing its application as a microbiota-based strategy for maintaining microbial homeostasis and preventing infections in the gastrointestinal and vaginal niches.
Il microbiota umano contribuisce a mantenere specifici equilibri fisiologici che preservano la salute dell'ospite. Quando si verifica uno squilibrio tra i microrganismi che popolano una parte del corpo, possono insorgere diverse malattie. L'asse intestino-vaginale rappresenta uno dei diversi modi in cui esiste una connessione tra l'intestino e un altro organo e la disbiosi che colpisce una comunità potrebbe influenzare anche l'altra. In questo contesto, l'uso di probiotici può fornire un'opportunità per aiutare a ripristinare l'equilibrio tra i microrganismi che compongono queste nicchie e prevenire la crescita di agenti patogeni. Questo studio si concentra sulla caratterizzazione genomica e fenotipica del Lactobacillus crispatus P 17631 per valutarne il potenziale utilizzo come ceppo probiotico per la salute intestinale e vaginale. Di conseguenza, è stata eseguita un'analisi dell'intero genoma per valutare la sicurezza e le proprietà funzionali del Lactobacillus crispatus P 17631 in conformità con le linee guida dell'EFSA, confermando l'assenza di fattori di virulenza e di geni di resistenza agli antibiotici trasferibili. Inoltre, è stato utilizzato un approccio di screening genomico per identificare i geni associati alla tolleranza allo stress, alla capacità di adesione e all'attività antimicrobica. Per confermare le proprietà probiotiche previste sulla base delle analisi genomiche, sono stati effettuati test fenotipici. La capacità di questo ceppo di sopravvivere nel tratto gastrointestinale è stata valutata esaminando (i) la stabilità del pH, (ii) la tolleranza ai sali biliari e (iii) la capacità di aderire alle cellule epiteliali, una caratteristica importante per stabilirsi e persistere sulle superfici mucose dell'ospite. Le analisi funzionali hanno determinato la capacità antimicrobica del ceppo, nonché la capacità di inibire la crescita di patogeni opportunistici associati alla disbiosi intestinale/vaginale, come Candida spp. L’integrazione dei dati genomici con quelli derivanti da analisi funzionali in vitro ha consentito di delineare un profilo complessivo dettagliato di Lactobacillus crispatus P17631. I risultati ottenuti supportano la sicurezza del ceppo e ne evidenziano il potenziale probiotico, fornendo al contempo una base conoscitiva per futuri studi finalizzati a valutare la sua possibile applicazione come approccio microbico per il mantenimento dell’equilibrio del microbiota e per la prevenzione delle infezioni sia a livello gastrointestinale sia vaginale.
Genomic-based studies characterize probiotics improving procedures for high-quality drug discovery and manufacturing
Arrigoni, Giulia
2026
Abstract
The human microbiota contributes to maintaining specific physiological equilibria that support the host’s health. When the balance among microorganisms inhabiting a particular body site is disrupted, various diseases may develop. The gut–vaginal axis is one example of the connections between the gut and other organs, where dysbiosis in one microbial community can influence the other. In this context, probiotics may represent a useful strategy to help restore microbial balance within these niches and to limit the excessive proliferation of pathogenic organisms. This study focuses on the genomic and phenotypic characterization of Lactobacillus crispatus P 17631 to evaluate its potential use as a probiotic strain for intestinal and vaginal health. Accordingly, whole-genome analysis was performed to assess the safety and functional properties of Lactobacillus crispatus P 17631 in compliance with EFSA guidelines, confirming the absence of virulence factors and transferable antibiotic resistance genes. Furthermore, a genomic screening approach was employed to identify genes associated with stress tolerance, adhesion capacity, and antimicrobial activity. To validate the probiotic potential predicted from genomic analyses, a series of phenotypic assays were conducted. The strain’s ability to withstand gastrointestinal conditions was evaluated by assessing (i) pH stability, (ii) tolerance to bile salts, and (iii) adhesion capacity to epithelial cells, a key trait for colonization and persistence on host mucosal surfaces. Functional assays further examined the strain’s antimicrobial activity and its ability to inhibit the growth of opportunistic pathogens associated with intestinal or vaginal dysbiosis, including Candida spp. The integration of genomic analyses with in vitro functional assays enabled the generation of a comprehensive characterization of Lactobacillus crispatus P17631. The resulting data support both the safety profile and the probiotic potential of this strain, and provide a foundation for future investigations aimed at assessing its application as a microbiota-based strategy for maintaining microbial homeostasis and preventing infections in the gastrointestinal and vaginal niches.| File | Dimensione | Formato | |
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https://hdl.handle.net/20.500.14242/362747
URN:NBN:IT:UNICATT-362747