A new heat shock gene, AgsA, which encodes a small chaperone involved in suppressing protein aggregation in Salmonella enterica serovar typhimurium.

ABSTRACT: We discovered a novel small heat shock protein (sHsp) named AgsA (aggregation-suppressing protein) in the thermally aggregated fraction from a Salmonella enterica serovar Typhimurium dnaK-null strain. The -10 and -35 regions upstream of the transcriptional start site of the agsA gene are characteristic of sigma(32)- and sigma(72)-dependent promoters. AgsA was strongly induced by high temperatures. The similarity between AgsA and the other two sHsps of Salmonella serovar Typhimurium, IbpA and IbpB, is rather low (around 30% amino acid sequence identity). Phylogenetic analysis suggested that AgsA arose from an ancient gene duplication or amplification at an early evolutionary stage of gram-negative bacteria. Here we show that overproduction of AgsA partially complements the DeltadnaK52 therm

SUBMITTER: Tomoyasu T 

PROVIDER: S-EPMC219406 | biostudies-literature | 2003 Nov

REPOSITORIES: biostudies-literature