Expression and secretion pattern of FljB of Salmonella enterica serovar Typhi in different culture conditions

• Flagellin of Salmonella is highly immunogenic and is a key protein recognized by the host immune system.
• SPI-1 inducing condition increases the secretion but not the expression level of FljB.
• SPI-2 inducing condition shut down the expression and consequential secretion of FljB.
• Salmonella may subvert the host's innate immune system through regulation of the expression and secretion of Flagellin.