The genomic basis of the Streptococcus thermophilus health-promoting properties

Abstract

Background Streptococcus thermophilus is a Gram-positive bacterium widely used as starter in the dairy industry as well as in many traditional fermented products. In addition to its technological importance, it has also gained interest in recent years as beneficial bacterium due to human health-promoting functionalities. The objective of this study was to inventory the main health-promoting properties of S. thermophilus and to study their intra-species diversity at the genomic and genetic level within a collection of representative strains. Results In this study various health-related functions were analyzed at the genome level from 79 genome sequences of strains isolated over a long time period from diverse products and different geographic locations. While some functions are widely conserved among isolates (e.g., degradation of lactose, folate production) suggesting their central physiological and ecological role for the species, others including the tagatose-6-phosphate pathway involved in the catabolism of galactose, and the production of bioactive peptides and gamma-aminobutyric acid are strain-specific. Most of these strain-specific health-promoting properties seems to have been acquired via horizontal gene transfer events. The genetic basis for the phenotypic diversity between strains for some health related traits have also been investigated. For instance, substitutions in the galK promoter region correlate with the ability of some strains to catabolize galactose via the Leloir pathway. Finally, the low occurrence in S. thermophilus genomes of genes coding for biogenic amine production and antibiotic resistance is also a contributing factor to its safety status. Conclusions The natural intra-species diversity of S. thermophilus, therefore, represents an interesting source for innovation in the field of fermented products enriched for healthy components that can be exploited to improve human health. A better knowledge of the health-promoting properties and their genomic and genetic diversity within the species may facilitate the selection and application of strains for specific biotechnological and human health-promoting purpose. Moreover, by pointing out that a substantial part of its functional potential still defies us, our work opens the way to uncover additional health-related functions through the intra-species diversity exploration of S. thermophilus by comparative genomics approaches.

Thermophilin 13: In Silico Analysis Provides New Insight in Genes Involved in Bacteriocin Production

“…In this study, both genomes were analysed independently. ** The identification name of the strains of Streptococcus thermophilus STH_CIRM_1048 and Streptococcus thermophilus STH_CIRM_1049 is related to the accession codes for genomes valid for the NCBI database; the same strains are reported as Streptococcus thermophilus CIRM-BIA1048 Streptococcus thermophilus CIRM-BIA1049 in citation [ 32 , 33 ]. *** GenBank code PEBN01000000.1 and PEBN01000052.1 both refer to Streptococcus macedonicus 19AS strain in NCBI database.…”

Applicable Strains, Processing Techniques and Health Benefits of Fermented Oat Beverages: A Review

“…The texture and flavor of fermented oat beverages dominate consumer acceptance and sustainability. Streptococcus thermophilus is derived from dairy products and considered a “Generally Recognized as Safe“ ingredient because of its ability to increase the viscosity of dairy products, Streptococcus thermophilus is often paired with Lactobacillus bulgaricus ( L. bulgaricus ) in some important fermented dairy products, including yogurt and cheese, resulting in its unique taste and stickiness [ 48 ]. Previous studies have shown that Streptococcus thermophilus TKM3 KKP 2030P is an efficient initial strain for the fermentation of plant-based raw materials.…”

Population and functional genomics of lactic acid bacteria, an important group of food microorganism: Current knowledge, challenges, and perspectives

“…Bulgaricus , and these genes confer survival advantage in the dairy environment (Bolotin et al., 2004; Pastink et al., 2009; Pfeiler & Klaenhammer, 2007). Moreover, most strain‐specific health‐promoting properties of S. thermophilus seem to have been likewise acquired via HGT events (Roux et al., 2022). The mechanism of HGT also seems to play a large role in the adaptability of Lact.…”