Article
Biotechnology & Applied Microbiology
Mylene Boulay, Coralie Metton, Christine Mezange, Lydie Oliveira Correia, Thierry Meylheuc, Veronique Monnet, Rozenn Gardan, Vincent Juillard
Summary: The study identified a new cell surface protease in Streptococcus thermophilus, which shows significant homology with a known protease in another bacterial species. This new protease, SepM, plays a role in cell wall metabolism and cell elongation, and its inactivation affects cell morphology.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
(2021)
Article
Agriculture, Dairy & Animal Science
Z. S. Xu, Z. Wang, X. Cui, Y. Liang, T. Wang, J. Kong
Summary: This study identified Ptrp-2 as an important protein for glutathione (GSH) transport in Streptococcus thermophilus through gene insertion and detection of intracellular GSH content. The experiment further demonstrated Ptrp-2's significance as a yogurt starter culture by showing that fermented milk hardly curds using a mutant strain in which Ptrp-2 was inactivated.
JOURNAL OF DAIRY SCIENCE
(2021)
Article
Microbiology
Rodrigo Achigar, Martina Scarrone, Genevieve M. Rousseau, Cecile Philippe, Felipe Machado, Valentina Duvos, Maria Pia Campot, Moira B. Dion, Yuyu Shao, Maria Julia Pianzzola, Sylvain Moineau
Summary: The study demonstrates that both CRISPR1 and CRISPR3 systems in Streptococcus thermophilus exhibit ectopic spacer acquisition, providing phage resistance. This phenomenon also appears to occur naturally in some strains of Streptococcus pyogenes, suggesting it is a general feature in type II-A systems.
Article
Microbiology
Ahmed Helal, Sara Pierri, Davide Tagliazucchi, Lisa Solieri
Summary: This study investigated the impact of simulated gastrointestinal digestion on whey protein concentrate (WPC) hydrolysates fermented with S. thermophilus strains. Fermentation enhanced protein hydrolysis and release of bioactive peptides, but some of the peptides could be broken down during digestion. WPC hydrolysates fermented with different strains showed varying biological activities, which were linked to the amount of bioactive peptides present.
Article
Agriculture, Multidisciplinary
Ling-Hui Kong, Zhi-Qiang Xiong, Yong-Jun Xia, Lian-Zhong Ai
Summary: This study developed three electroporation transformation methods for S. thermophilus S-3, optimizing various parameters to enhance the transformation efficiency. Transcriptional analysis showed up-regulation of competence genes after optimization, leading to increased transformation efficiency. Overexpression of the competence gene comEA resulted in a 14-fold increase in transformation efficiency, showing potential for the development of desirable characteristics strains.
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
(2021)
Article
Microbiology
Yunchao Wa, Ryan Matthew Chanyi, Hanh Thi Hong Nguyen, Ruixia Gu, Li Day, Eric Altermann
Summary: Lactic acid bacteria, such as Streptococcus thermophilus, produce extracellular polysaccharides (EPS) that enhance the creaminess and mouthfeel of fermented foods like yogurt. Traditional methods underestimate the amount of EPS produced, but the addition of a proteolytic step prior to extraction significantly improves yield. This study validates the effectiveness of Method C for extracting EPS in fermented milk samples from different strains of S. thermophilus.
MICROBIOLOGY SPECTRUM
(2022)
Article
Biochemistry & Molecular Biology
Yang Zhou, Yanhua Cui, Chao Suo, Qian Wang, Xiaojun Qu
Summary: The study showed that EPS-M2 produced by Streptococcus thermophilus CS6 exhibited good rheology, thermostability, and antioxidant activity, mainly composed of galactose, arabinose, and glucose. The EPS-M2 has potential applications in the food industry as a natural thickener, stabilizer, and antioxidant agent.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2021)
Review
Food Science & Technology
Ruiting Zhao, Zouquan Chen, Jie Liang, Jiaxin Dou, Fangyu Guo, Zhenshang Xu, Ting Wang
Summary: This review discusses the physiological studies on the traditional starter Streptococcus thermophilus and introduces a toolbox for gene expression and genome editing. These tools can be used for the development of functionalized foods and therapeutic molecules.
Article
Biochemistry & Molecular Biology
Lisa Solieri, Marta Valentini, Alice Cattivelli, Laura Sola, Ahmed Helal, Serena Martini, Davide Tagliazucchi
Summary: In this study, Lactobacillus helveticus and Streptococcus thermophilus strains isolated from Parmigiano Reggiano production were evaluated for their ability to ferment whey protein concentrate (WPC) and release bioactive peptides. The results showed that WPC fermented with S. thermophilus RBC06 had the highest antioxidant activity and inhibitory activities against angiotensin-converting enzyme and dipeptidyl-peptidase-IV. Several bioactive peptides, including angiotensin-converting enzyme inhibitors, were identified and quantified. This study paves the way for the potential use of S. thermophilus RBC06 as a new bioactive peptide producer and the application of WPC hydrolysates in designing whey-based beverages with enhanced health properties.
PROCESS BIOCHEMISTRY
(2022)
Article
Biotechnology & Applied Microbiology
Mei Han, Yanfeng Wu, Xiaojuan Guo, Lili Jiang, Xin Wang, Zhonghui Gai
Summary: This study analyzed the characteristics of Streptococcus thermophilus strains and optimized a universal culture medium for their growth. The study also discovered symbiotic or competitive relationships between different strains and developed an optimized mixture of symbiotic strains to produce fermented milk with desirable texture and low post-acidification.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2022)
Review
Food Science & Technology
Yan-Yan Huang, Yun-Hui Lu, Xin-Tong Liu, Wei-Tong Wu, Wen-Qi Li, Shu-Qin Lai, Rana Muhammad Aadil, Muhammad Shahid Riaz Rajoka, Lang-Hong Wang, Xin-An Zeng
Summary: Lactic acid bacteria (LAB) are non-respiring, non-spore-forming bacteria that produce lactic acid as the main product of carbohydrate fermentation. Some strains of LAB are probiotics that play important roles in food processing and safety, as well as in maintaining human health. This article summarizes the isolation and identification, safety assessments, and metabolic properties of Streptococcus thermophilus, a species of LAB, and discusses its functional properties, applications in fermented product production, new perspectives, and limitations, in order to facilitate future research and application of S. thermophilus.
FOOD REVIEWS INTERNATIONAL
(2023)
Article
Chemistry, Applied
Xin Pan, Jing Li, Fei Lao, Xujie Hou, Lin Gao, Jihong Wu
Summary: The health benefits of fruit products fermented with probiotics are partly due to the increased content of phenolic compounds. This study investigated the effect of in vitro dynamic gastrointestinal digestion on the release of phenolic compounds and changes in the antioxidant activity of jujube puree fermented with Streptococcus thermophilus. Fermentation with Streptococcus thermophilus significantly increased the content of most phenolic compounds in jujube puree and improved its antioxidant capacity during gastrointestinal digestion.
Article
Food Science & Technology
Yu Li, Ye Wang, Baolei Li, Baochao Hou, Weilian Hung, Jian He, Yujun Jiang, Yu Zhang, Chaoxin Man
Summary: The metabolic utilization of different carbon sources by Streptococcus thermophilus JM905 was analyzed, and changes in fermentation characteristics of its fermented milk were investigated. The study clarified the changes in key metabolites and determined the quality nutrient contents of protein, amino acids, and fat in the fermented milk.
Article
Food Science & Technology
Zhenxiang Xu, Xiaojing Li, Xingfang Tian, Suzhen Yang, Yan Li, Zhengguang Li, Tingting Guo, Jian Kong
Summary: This study identified an eps gene cluster in the genome of Streptococcus thermophilus CGMCC 7.179, a traditional yogurt starter. After purification, three main components ST-ESP1, ST-EPS2, and ST-EPS3 consisting of mannose, glucuronic acid, galacturonic acid, glucose, and N-acetylglucosamine were obtained. ST-EPS2 showed stronger antioxidant activity and upregulated the transcription levels of Nrf2, suggesting its potential as a natural antioxidant in the food industry.
LWT-FOOD SCIENCE AND TECHNOLOGY
(2023)
Article
Biochemistry & Molecular Biology
Zhiyuan Xu, Qingbin Guo, Hui Zhang, Zhiqiang Xiong, Xiumin Zhang, Lianzhong Ai
Summary: The application of Streptococcus thermophilus S-3 in yogurt production led to the generation of EPS-S3 with high apparent viscosity and quality, when co-cultured with Lactobacillus delbrueckii, it significantly increased the acidifying rate and improved the rheological properties compared to using Lactobacillus bulgaricus only. The production mechanism of EPS-S3 was discussed for potential applications in milk production.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2021)