Co-culture affects protein profile and technological properties heat tolerance of Lactobacillus delbrueckii subsp. lactis and Bifidobacterium longum.

SÁNCHEZ, B.; BURNS, P.; RUIZ, L.; BINETTI, A. G.; VINDEROLA, C. G.; REINHEIMER, J. A.; MARGOLLES, A.; RÚAS-MADIEDO, P.; DE LOS REYES-GAVILÁN, C.

FOOD RESEARCH INTERNATIONAL

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2012

0963-9969

Some strains of the genus Bifidobacterium are considered probiotics and can be added as adjunct cultures to functional dairy products. Lactobacillus delbrueckii subsp. lactis is used as a starter in food fermentations. The influence of co-culturing strains Bifidobacterium longum NCIMB 8809 and Lactobacillus delbrueckii subsp. lactis 193 on the physiology and heat tolerance of these microorganisms was studied. 2DE coupled to MS protein analysis allowed the identification of several proteins from each bacterium whose expression changed when cells were grown in compartmentalized co-cultures compared to mono-cultures. These include proteins belonging to several functional categories such as carbohydrates, amino acids, vitamins and nucleotide metabolism, transcription and translation, protein folding, sorting and degradation, and energy metabolism. Remarkably, changes occurring in the carbohydrate metabolism in both strains focused on the increase of ATP synthesis and on the optimization of galactose utilization in a cooperative way. The production of stress response chaperones was enhanced in both strains and was related with increased survival to heat shock, a technologically suitable property in the manufacture of some dairy products. Differential production of peroxiredoxin and LuxS protein occurred in B. longum which suggests metabolic adjustments in response to the availability of fermentable substrates due to the presence of L. delbrueckii subsp. lactis. An increase of enzymes related to peptidoglycan biosynthesis was found in B. longum, probably in response to the metabolic activity associated with the higher growth rates of L. delbrueckii subsp. bulgaricus. This study provides the first insight in understanding communication between B. longum and L. delbrueckii subsp. lactis.