title: New Insights into Various Production Characteristics of Streptococcus thermophilus Strains.
abstract: Streptococcus thermophilusis one of the most valuable homo-fermentative lactic acid bacteria, which, for a long time, has been widely used as a starter for the production of fermented dairy products. The key production characteristics ofS. thermophilus, for example the production of extracellular polysaccharide, proteolytic enzymes and flavor substances as well as acidifying capacity etc., have an important effect on the quality of dairy products. The acidification capacity of the strains determines the manufacturing time and quality of dairy products. It depends on the sugar utilization ability of strains. The production of extracellular polysaccharide is beneficial for improving the texture of dairy products. Flavor substances increase the acceptability of dairy products. The proteolytic activity of the strain influences not only the absorption of the nitrogen source, but also the formation of flavor substances. Different strains have obvious differences in production characteristics via long-time evolution and adaptation to environment. Gaining new strains with novel and desirable characteristics is an important long-term goal for researchers and the fermenting industry. The understanding of the potential molecular mechanisms behind important characteristics of different strains will promote the screening and breeding of excellent strains. In this paper, key technological and functional properties of differentS. thermophilusstrains are discussed, including sugar metabolism, proteolytic system and amino acid metabolism, and polysaccharide and flavor substance biosynthesis. At the same time, diversity of genomes and plasmids ofS. thermophilusare presented. Advances in research on key production characteristics and molecular levels ofS. thermophiluswill increase understanding of molecular mechanisms of different strains with different important characteristics, and improve the industrialization control level for fermented foods.
authors.affiliation: Department of Food Science and Engineering, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150090, China. yhcui@hit.edu.cn.
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Cui
authors.affiliation: Department of Food Science and Engineering, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150090, China. xutingting@gmail.com.
authors.forename: Tingting
authors.initials: T
authors.lastname: Xu
authors.affiliation: Institute of Microbiology, Heilongjiang Academy of Sciences, Harbin 150010, China. qvxiaojun@163.com.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Qu
authors.affiliation: Department of Food Science and Engineering, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150090, China. tonghu1992715@gmail.com.
authors.forename: Tong
authors.initials: T
authors.lastname: Hu
authors.affiliation: Department of Food Science and Engineering, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150090, China. jiangxu2016@gmail.com.
authors.forename: Xu
authors.initials: X
authors.lastname: Jiang
authors.affiliation: Department of Food Science and Engineering, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150090, China. zhaochunyuhit@yeah.net.
authors.forename: Chunyu
authors.initials: C
authors.lastname: Zhao
mesh_terms: D000818:Animals; D050260:Carbohydrate Metabolism; D005285:Fermentation; D005516:Food Microbiology / Q000639:trends*; D007218:Industrial Microbiology / Q000639:trends; D008892:Milk / Q000737:chemistry; D048249:Streptococcus thermophilus / Q000145:classification / Q000235:genetics / Q000502:physiology*
keywords: Streptococcus thermophilus; genomics; plasmid; production characteristics