Genome comparison and physiological characterization of eight Streptococcus thermophilus strains isolated from Italian dairy products.

Genome comparison and physiological characterization of eight Streptococcus thermophilus strains isolated from Italian dairy products. Food Microbiol. 2017 May;63:47-57 Authors: Vendramin V, Treu L, Campanaro S, Lombardi A, Corich V, Giacomini A Abstract Eight Streptococcus thermophilus strains of dairy origin isolated in Italy were chosen to investigate autochthonous bacterial diversity in this important technological species. In the present study a comparative analysis of all the 17 S. thermophilus genomes publicly available was performed to identify the core and the variable genes, which vary among strains from 196 to 265. Additionally, correlation between the isolation site and the genetic distance was investigated at genomic level. Results highlight that the phylogenetic reconstruction differs from the geographical strain distribution. Moreover, strain M17PTZA496 has a genome of 2.15 Mbp, notably larger than that of the others, determined by lateral gene transfer (including phage-mediated incorporation) and duplication events. Important technological characters, such as growth kinetics, bacteriocin production, acidification kinetics and surface adhesion capability were studied in all the Italian strains. Results indicate a wide range of variability in adhesion properties that significantly clustered strains into four groups. Genomic differences among strains in relation to these characters were identified but a clear correlati...
Source: Food Microbiology - Category: Food Science Authors: Tags: Food Microbiol Source Type: research