Abstract: Shewanella putrefaciens is a cold-adapted microorganism, which is considered as one of the most important species causing spoilage of sea foods. This study aimed to elucidate the molecular mechanism of the response to cold stress in S. putrefaciens. The differential expression of the proteome in S. putrefaciens DSM6067 at different temperatures (30, 10 and 4 ℃) was investigated using a label-free quantitative proteomic approach and two-dimensional liquid chromatography-tandem mass spectrometry (2D LC-MS/MS). The results showed that more proteins were expressed when the strain was cultured at lower temperatures. A total of 2 165 protein bands were obtained, 1 739, 1 761 and 1 832 of them being identified at 30,10 and 4 ℃, respectively. Bioinformatics analysis revealed that these proteins participated in several gene ontology (GO) categories and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. According to GO analysis, the functional categories were dominated by metabolic activity, catalytic activity, and molecular binding. Although the expression levels of proteins participated in fatty acid metabolism pathway were relatively lower in all samples among the whole metabolic pathways, there were significant differences in protein expression at different culture temperatures and the lower the temperature, the higher the expression level.

Key words: temperature, Shewanella putrefaciens, proteomics, GO categories, KEGG pathways