Change of free amino acids in M17 medium after growth of Streptococcus thermophilus and identification of a glutamine transport ATP-binding protein

摘要: Free amino acid concentrations changes were evaluated in M17 medium after growth of Streptococcus thermophilus. Three strains (ITGST80, ITGST82, CNRZ407) with technological differences tested. The extracellular the exhibited a large decrease concentration leucine, glutamic acid, lysine, alanine, arginine and aspartic an increase methionine, glutamine histidine. change was most significant for ITGST82 strain. Comparing 2D-PAGE protein profiles strains, one overexpressed grown milk detected. N-terminal sequence this determined 18 residues showed homology to transport ATP-binding proteins. Thus, S. thermophilus, enriched glutamine, which may have potentially interesting nutritional consequences products fermented by organism.