Growth and transcriptional response of Salmonella Typhimurium LT2 to glucose-lysine-based Maillard reaction products generated under low water activity conditions

Abstract This study reports the growth and transcriptional responses of Salmonella Typhimurium LT2 to Maillard reaction products (MRPs) generated in a simulation of the reaction during food processing and storage. Maillard reactions between N - α -acetyl-lysine and glucose were stopped at 4, 23, or 143 h to generate sub-samples with prevailing Amadori compound, advanced glycation end products (AGEs), or melanoidins, respectively. When used as the only carbon source, MRPs' disappearance occurred during S . Typhimurium secondary logarithmic growth phase after the glucose available in the MRP reaction mixtures was exhausted. Of the three MRP sub-samples, the Amadori compound was the preferred carbon source (98% disappearance). Decreases in AGEs (37%) and melanoidins (15%) also occurred. Transcription profiles of cells grown on the MRPs revealed predominant up-regulation of genes associated with the functional groups of energy metabolism, fatty and phospholipid metabolism, cellular process, and regulatory functions, and general down-regulation of the genes in the groups of amino acid biosynthesis, protein synthesis and transcription, transport and binding proteins, and DNA metabolism.