Phenotypic and genotypic evaluation of wakame assimilation ability in Ligilactobacillus salivarius strains isolated from wakame fed pigs

ELEAN, MARIANO; ALBARRACÍN, LEONARDO; RAYA TONETTI, FERNANDA; ORTIZ MOYANO, RAMIRO; DENTICE MAIDANA, STEFANIA; KITAZAWA, HARUKI; VILLENA, JULIO

San Miguel de Tucumán

Simposio; 7ma edición del Simposio Argentino de Jóvenes Investigadores en Bioinformática; 2022

Argentine Regional Student Group (RSG-Argentina)

Wakame contains some bioactive components including fucoidan, alginic acid, omega 3fatty acids, vitamins, and minerals, which has been reported to have beneficial effects inthe human host. Among the beneficial effects attributed to wakame are its antibacterial,antioxidant and anti-inflammatory functions. Recently, we demonstrated that feedingpigs with wakame improved gastrointestinal immunity and induced a significant increasein the abundance of members of the Lactobacillus family, specially Ligilactobacillussalivarius. To determine whether the beneficial immunological effects of wakame wereassociated to the increment of L. salivarius strains, we isolated and characterized strainsfrom wakame-fed pigs belonging to this species. The complete genome of eight selectedL. salivarius strains (named FFIG) were sequenced and the functional and genomiccharacterization of those strains revealed that their immunomodulatory and adhesioncapabilities are a strain-specific characteristic. In this work we aimed to furthercharacterize the L. salivarius FFIG strains studying their wakame assimilation abilities byphenotypic and genotypic approaches. A prolonged fermentation experiment wasdesigned to investigate the consumption of the saccharides by the FFIG strains in twodifferent wakame broths (wakame leaf and wakame stalk). TLC analysis showed that theeight FFIG strains were able to utilize the saccharides contained in enzyme-treatedwakame. The strains had different preferences for the two wakame broths. In wakameleaf, FFIG58, FFIG24 and FFIG63 were the strains with the highest ability to grow, whereasFFIG130 and FFIG79 were the strains with the lowest bacterial counts. In wakame stalk,the strains FFIG60, FFIG79 and FFIG130 stood out over the eight strains with the highestviable counts, whereas the FFIG58 have the lowest counts. It was reported that L.salivarius strains have different abundance of genes belonging to glycosyltransferases andglycosylhydrolases families, and that the set of enzymes determine the carbon sourcesthat each strain can use for growing. Then, we evaluated the abundance of genesbelonging to glycosylhydrolases families among the FFIG strains and compared themwith other L. salivarius strains of animal origin. The clustering analysis considering thenumbers and types of glycosylhydrolases showed that strains FFIG58, FFIG63, FFIG79 andFFIG124 had a significant higher abundance of enzymes from the families GH25 and GH13,when compared with all the other L. salivarius strains. Finally, we performed comparativegenomic studies between the FFIG strains and other strains isolated from human andporcine origins. We found a core genome compound of 710 genes, and there was nocorrelation between the number of unique genes and the difference in the phenotypes.To the best of our knowledge, this is the first study that evaluated wakame assimilationcapacity of L. salivarius strains using phenotypic and genomic approaches.