Helicobacter pylori GroES (HspA)

Helicobacter pylori GroES, also known as HspA, is a specialized co-chaperonin that is essential for the survival and pathogenesis of the bacterium in the human stomach. Unlike standard GroES proteins, HspA contains a unique C-terminal domain rich in histidine and cysteine residues, which allows it to bind nickel ions with high affinity. This dual-function protein acts as a molecular chaperone for protein folding in conjunction with GroEL and serves as a nickel chaperone required for the maturation of nickel-dependent enzymes, such as [NiFe] hydrogenase and urease. Urease is a critical virulence factor that neutralizes gastric acid, enabling H. pylori to colonize the gastric mucosa. Bismuth-containing drugs, such as bismuth subsalicylate and colloidal bismuth subcitrate, are known to interact with HspA by displacing nickel ions, thereby inhibiting the maturation of essential enzymes and contributing to bacterial eradication. Due to its essentiality and high immunogenicity, HspA is also a primary candidate for the development of recombinant vaccines and novel antimicrobial agents targeting nickel homeostasis.

Other names

Heat shock protein AHspA10 kDa chaperoninGroES homologNickel-binding heat shock protein

Inhibition of protein folding and disruption of nickel-dependent enzyme maturation through metal displacement or chaperone inhibition