Dissecting the interference effect of L. gasseri over Candida species exploring insights gathered from exoproteomic and exometabolomic analyses

November 21, 2025

The Lactobacillus genus includes Gram-positive species relevant to human health, food preservation and industrial applications, characterised by their ability to produce lactic acid. In the food industry, these microorganisms contribute to improving flavour, texture, shelf life and the nutritional value of products. This study aimed to investigate the interaction between Lactobacillus gasseri and pathogenic Candida species (C. albicans and C. glabrata), assessing how acetate modulates the anti-Candida activity exhibited by this bacterium The results showed that the presence of acetate in the co-culture medium increased the anti-Candida effect of L. gasseri. This effect tended to be stronger in intestinal strains, although strain-specific differences were also observed. To explore the mechanisms involved, the co-culture supernatant was fractionated into metabolic and protein-enriched components. The strongest inhibitory activity was observed in the metabolite-enriched fractions obtained with 10 kDa filters. When 3 kDa filters were used, the opposite pattern was observed, with higher anti-Candida activity detected in protein-enriched fractions. Exoproteomic and exometabolomic analyses enabled the identification of candidate proteins and metabolites potentially responsible for the observed activity, suggesting that the anti-Candida effect results from the combined action of multiple molecules produced by L. gasseri and modulated by acetate. These findings contribute to a better understanding of relevant microbial interactions within the vaginal microbiome and may support the development of new therapeutic strategies against Candida infections, particularly important in the context of increasing antifungal resistance.

Authors in the community:

• 

  L

  Lara Margarida Perdigão Silva de Sousa

  ist1110963

Supervisors of this institution:

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  N

  Nuno Gonçalo Pereira Mira

  ist148703

industrial-biotechnology - Industrial Biotechnology

eng - English

Instituto Superior Técnico