In this study, we investigated the effect of water activity on transcriptome and proteome of Aspergillus flavus spore germination.we investigated the most important protein in PPI network in proteome, the S-adenosylmethionine-dependent methyltransferase superfamily domain-containing protein. Studies on S-adenosylmethionine (SAM)-dependent methyltransferases showed that it is crucial in cell signaling, metabolism and epigenetic programming