Project description:Vibrio (V.) parahaemolyticus is the leading cause of seafood borne gastro-intestinal infections in humans worldwide. It is widely found in marine environments and is isolated frequently from seawater, estuarine waters, sediments and raw or insufficiently cooked seafood. Within the food chain, V. parahaemolyticus encounters different temperature conditions that might alter the metabolism and pathogenicity of the bacterium. In this study, we performed gene expression profiling of V. parahaemolyticus RIMD 2210633 after exposure to 4°C, 15°C, 20°C, 37°C and 42°C to describe the cold and heat shock response. Analysis of transcriptomics data resulted in differential expression of 19 genes at 20°C, 193 genes at 4°C, 625 genes at 42°C and 639 genes at 15°C. Thus the highest portion of significantly expressed genes was observed at 15°C and 42°C with 13.3% and 13%, respectively. Genes of many functional categories were highly regulated even at lower temperatures. Our results showed that virulence associated genes (tdh1, tdh2, toxR, toxS, vopC, T6SS1, T6SS2) remained largely unaffected by heat or cold stresses. Along with folding and temperature shock depending systems, an overall temperature depended regulation of expression could be shown. Particularly the energy metabolism was affected most by changed temperatures. Whole-genome gene expression studies of food related pathogens such as V. parahaemolyticus reveal how these pathogens react to stress impacts for prediction of its behaviour under conditions like storage and transport.
Project description:Vibrio (V.) parahaemolyticus is the leading cause of seafood borne gastro-intestinal infections in humans worldwide. It is widely found in marine environments and is isolated frequently from seawater, estuarine waters, sediments and raw or insufficiently cooked seafood. Within the food chain, V. parahaemolyticus encounters different temperature conditions that might alter the metabolism and pathogenicity of the bacterium. In this study, we performed gene expression profiling of V. parahaemolyticus RIMD 2210633 after exposure to 4°C, 15°C, 20°C, 37°C and 42°C to describe the cold and heat shock response. Analysis of transcriptomics data resulted in differential expression of 19 genes at 20°C, 193 genes at 4°C, 625 genes at 42°C and 639 genes at 15°C. Thus the highest portion of significantly expressed genes was observed at 15°C and 42°C with 13.3% and 13%, respectively. Genes of many functional categories were highly regulated even at lower temperatures. Our results showed that virulence associated genes (tdh1, tdh2, toxR, toxS, vopC, T6SS1, T6SS2) remained largely unaffected by heat or cold stresses. Along with folding and temperature shock depending systems, an overall temperature depended regulation of expression could be shown. Particularly the energy metabolism was affected most by changed temperatures. Whole-genome gene expression studies of food related pathogens such as V. parahaemolyticus reveal how these pathogens react to stress impacts for prediction of its behaviour under conditions like storage and transport. Temperature induced gene expression was detected in total bacterial RNA of V. parahaemolyticus. Five different temperatures (4°C, 15°C, 20°C, 37°C, 42°C) were used in at least 3 biological replicates (4 replicates for 37°C). Gene expression at 37°C was used for normalization.