Extracellular bacterial glyceraldehyde-3-phosphate dehydrogenase (GAPDH)

Extracellular bacterial glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a multifunctional moonlighting protein that serves as a critical virulence factor for various pathogens, including Streptococcus agalactiae, Streptococcus pneumoniae, Escherichia coli, and Klebsiella pneumoniae. While its primary intracellular role is in the glycolytic pathway, its surface-localized or secreted form facilitates bacterial adhesion to host tissues by binding to extracellular matrix components like plasminogen, fibrinogen, and laminin. It also plays a significant role in immune evasion by inducing anti-inflammatory cytokines such as IL-10, inhibiting the classical complement pathway through C1q binding, and triggering apoptosis in host macrophages. In some species, it further contributes to pathogenesis by scavenging iron from host hemoglobin. Due to its essentiality for bacterial survival and its prominent role in infection, it is a promising target for vaccines and novel antimicrobial agents. However, the high structural conservation between bacterial and human GAPDH poses a significant challenge for the development of selective small-molecule inhibitors, requiring the targeting of unique bacterial epitopes to avoid host toxicity.

Other names

Surface-localized GAPDHMoonlighting GAPDHSecreted GAPDHStreptococcal surface dehydrogenaseSDHGapCGapA

Inhibition of glycolytic activity to disrupt bacterial energy metabolism, neutralization of surface-bound protein to prevent host tissue adhesion, and blocking of immunomodulatory interactions to restore host immune responses.