Beta-keto-L-gulonate decarboxylase (BKGD)

Beta-keto-L-gulonate decarboxylase (BKGD), also known as ester hydrolase C11orf54, is a highly conserved enzyme present in humans and other metazoans. It catalyzes the decarboxylation of β-keto-L-gulonate to L-xylulose, thus completing the pentose pathway and explaining the molecular origin of L-xylulose in human metabolism. This alternative route for pentose sugar conversion is evolutionarily ancient and offers a metabolic tradeoff relevant to ascorbate (vitamin C) biosynthesis. Structurally, BKGD features a zinc-coordinating motif and belongs to the metallo-β-lactamase fold protein superfamily. It also has weak in vitro ester hydrolase activity but is now primarily defined as a decarboxylase by recent studies. Beyond its metabolic role, BKGD/C11orf54 regulates cell proliferation, DNA damage response, and repair in mammalian cells, making it a biomarker for several cancers. The protein is cytoplasmic, with enrichment in kidney and liver, and interacts with various signaling and structural proteins relevant to cellular homeostasis. While direct pharmacological targeting is not yet established, modulation of its pathway (such as autophagy inhibitors) reveals therapeutic potential and safety concerns tied to genotoxic stress.

Other names

Ester hydrolase C11orf54C11orf54PTD012PTOD012LP4947MEEPEpididymis secretory sperm binding protein

Bafilomycin A1 rescues C11orf54 knockdown-induced DNA damage by inhibiting chaperone-mediated autophagy, suggesting a functional, indirect mechanism via CMA inhibition