Streptococcus thermophilus: Un chasis de próxima generación para personalizar exopolisacáridos con azúcares raros

As a pivotal strain in the fermentation industry, Streptococcus thermophilus produces exopolysaccharides (EPS) that not only enhance the texture and stability of dairy products but also confer various health benefits. The composition and structure of polysaccharides are closely related to their physicochemical characteristics and biological functions. This review systematically summarizes the composition and structure and industrial applications (functional components and food additives) of S. thermophilus EPS. Rare sugars endow common EPS with unique bioactivities and higher value. S. thermophilus has become a prospective cell factory for customizing EPS containing rare sugars owing to its food-grade safety, clear genetic characteristics of EPS synthesis pathway, unique natural transformation competence, and abundant endogenous clustered regularly interspaced short palindromic repeats interference systems. The core innovation of this review lies in the in-depth exploration of utilizing these advantages and advanced metabolic engineering strategies for enabling or enhancing the synthesis of S. thermophilus EPS containing fucose, rhamnose, and uronic acids. This review offers valuable insights for promoting S. thermophilus as a next generation cell factory and the application of ST-EPS in the food and pharmaceutical industries.