probiotic
Food MicrobiologyGeneration of Lactose- and Protease-Positive Probiotic Lacticaseibacillus rhamnosus GG by Conjugation with Lactococcus lactis NCDO 712Probiotic strain Lacticaseibacillus rhamnosus GG (LGG) is widely sold on the market as a probiotic or added as a supplement in dairy foods because of its benefits in human health. However, due to the deficiency of lactose and casein utilization, LGG does not grow well in milk.
MethodsPortable CRISPR-Cas9N System for Flexible Genome Engineering in Lactobacillus acidophilus, Lactobacillus gasseri, and Lactobacillus paracaseiThis work describes the development of a lactobacillus CRISPR-based editing system for genome manipulations in three Lactobacillus species belonging to the lactic acid bacteria (LAB), which are commonly known for their long history of use in food fermentations and as indigenous members of healthy microbiotas and for their emerging roles in human and animal commercial health-promoting applications. We exploited the established...
Microbial EcologyMucin as a Functional Niche Is a More Important Driver of In Vitro Gut Microbiota Composition and Functionality than Akkermansia muciniphila SupplementationResearch into the identification of biomarkers for gut health and ways to modulate the microbiota composition and activity to improve health has put Akkermansia muciniphila in the spotlight. As a mucin degrader, A. muciniphila colonizes the interesting but not fully described host-glycan degradation niche. Much of research concerning A. muciniphila...
Enzymology and Protein EngineeringAn 1,4-α-Glucosyltransferase Defines a New Maltodextrin Catabolism Scheme in Lactobacillus acidophilusThe degradation of starch in the small intestine generates short linear and branched α-glucans. The latter are poorly digestible by humans, rendering them available to the gut microbiota, e.g., lactobacilli adapted to the small intestine and considered beneficial to health. This study unveils a previously unknown scheme of maltooligosaccharide (MOS) catabolism via the concerted activity of an 1,4-α-glucosyltransferase together with a...
Genetics and Molecular Biology | SpotlightPutative Adhesion Factors in Vaginal Lactobacillus gasseri DSM 14869: Functional CharacterizationLactobacilli are known to contribute to the maintenance of a healthy vaginal microbiota and some are selected as probiotics for the prevention or treatment of urogenital diseases, such as bacterial vaginosis. However, the molecular mechanisms for these health-promoting effects are not fully understood. Here, we functionally identified three cell surface factors of a ...
Microbial Ecology | SpotlightAn In Vitro Enrichment Strategy for Formulating Synergistic SynbioticsThis study describes an in vitro enrichment method to formulate synergistic synbiotics that have potential for establishing autochthonous strains across multiple individuals. The rationale for this approach—that the chance of survival of a bacterial strain is improved by providing it with its required resources—is based on classic ecological theory. From these experiments, a human-derived strain,...
Meeting Presentation | SpotlightExploiting Prophage-Mediated Lysis for Biotherapeutic Release by Lactobacillus reuteriLactic acid bacteria (LAB) have been explored as potential biotherapeutic vehicles for the past 20 years. To secrete a therapeutic in the extracellular milieu, one typically relies on the bacterial secretion pathway, i.e., the Sec pathway. Overexpression of a secreted protein can overload the secretory pathway and impact the organism’s fitness, and optimization of the signal peptide is also required to maximize the efficiency of the...
Meeting PresentationGut Symbionts Lactobacillus reuteri R2lc and 2010 Encode a Polyketide Synthase Cluster That Activates the Mammalian Aryl Hydrocarbon ReceptorTemporary changes in the composition of the microbiota, for example, by oral administration of probiotics, can modulate the host immune system. However, the underlying mechanisms by which probiotics interact with the host are often unknown. Here, we show that Lactobacillus reuteri R2lc and 2010 harbor an orthologous PKS gene cluster that activates the aryl hydrocarbon...
Food MicrobiologySurface Layer of Lactobacillus helveticus MIMLh5 Promotes Endocytosis by Dendritic CellsBeneficial microbes may positively affect host physiology at various levels, e.g., by participating in immune system maturation and modulation, boosting defenses and dampening reactions, thus affecting the whole homeostasis. As a consequence, the use of probiotics is increasingly regarded as suitable for more extended applications for health maintenance, not only microbiota balancing. This implies a deep knowledge of the mechanisms and...
Microbial EcologyDissecting the Evolutionary Development of the Species Bifidobacterium animalis through Comparative Genomics AnalysesThe majority of characterized B. animalis strains have been isolated from human fecal samples. In order to explore genome variability within this species, we isolated 15 novel strains from the gastrointestinal tracts of different animals, including mammals and birds. The present study allowed us to reconstruct the pangenome of this taxon, including the genome contents...