Mixed-Culture Transcriptome Analysis Reveals the Molecular Basis of Mixed-Culture Growth in Streptococcus thermophilus and Lactobacillus bulgaricus

• DOI: 10.1128/aem.01122-10
• Publication Date: 2010-10-02T02:45:23Z
• Authors: Sander Sieuwerts; Douwe Molenaar; Sacha A. F. T. va...; Marke Beerthuyzen; Marc J. A. Stevens; Patrick W. M. Jan...; Colin J. Ingham; Frank A. M. de Bok; Willem M. de Vos; Johan E. T. van H...
• Keywords: lactic-acid bacteria; 2. Zero hunger; 0301 basic medicine; milk; 0303 health sciences; Gene Expression Profiling; pathways; Fatty Acids; delbrueckii; microarray data; Yogurt; United States; plantarum; proteinases; yogurt; Lactobacillus; 03 medical and health sciences; Purines; Fermentation; identification; NCMLS 4: Energy and redox metabolism; Streptococcus thermophilus; Amino Acids; metabolism

Many food fermentations are performed using mixed cultures of lactic acid bacteria. Interactions between strains key importance for the performance these fermentations. Yogurt fermentation by Streptococcus thermophilus and Lactobacillus bulgaricus (basonym, delbrueckii subsp. bulgaricus) is one best-described mixed-culture These species believed to stimulate each other's growth exchange metabolites such as folic carbon dioxide. Recently, postgenomic studies revealed that an upregulation biosynthesis pathways nucleotides sulfur-containing amino acids part global physiological response in S. thermophilus, but in-depth molecular analysis both remains be established. We report here application transcriptome profiling a systematic effect interaction-related compounds on growth, which allowed us unravel responses associated with batch milk CNRZ1066 L. ATCC BAA-365. The results indicate interactions bacteria primarily related purine, acid, long-chain fatty metabolism. support model formic provided thermophilus. Proteolysis supplies insufficient meet biosynthetic demands sulfur branched-chain acids, becomes clear from genes culture. Moreover, involved iron uptake affected coding exopolysaccharide production were upregulated organisms culture compared monocultures. confirmation previously identified different strain combination demonstrates their generic value. In addition, allows deeper understanding ecology this important industrial process.