Urease (Canavalia ensiformis) (JBU)

Jack bean urease (JBU), derived from the seeds of Canavalia ensiformis, is a high-molecular-weight, nickel-dependent metalloenzyme that catalyzes the hydrolysis of urea into ammonia and carbon dioxide (UniProt: P07374). It holds historical significance as the first enzyme ever crystallized, a feat that confirmed the proteinaceous nature of enzymes (Sumner, 1926). While JBU is a plant protein, it serves as the primary structural and functional prototype for bacterial ureases, which are critical virulence factors in human pathogens like Helicobacter pylori and Proteus mirabilis (PubMed: 24571459). These bacterial enzymes contribute to the pathogenesis of gastric ulcers, stomach cancer, and the formation of infection-induced kidney stones by elevating local pH levels. Consequently, JBU is widely utilized in drug discovery as a target for screening urease inhibitors, such as acetohydroxamic acid, which are used to treat infections caused by urea-splitting bacteria (PubChem: CID 114765). Research into JBU inhibitors aims to develop therapeutic agents that can mitigate the harmful effects of excessive ammonia production in both medical and agricultural settings.

Other names

Jack bean ureaseUrea amidohydrolaseCanavalia ensiformis urease

Inhibitors typically function by coordinating with the binuclear nickel center in the active site, thereby blocking the binding of the urea substrate and preventing its hydrolysis into ammonia and carbon dioxide (PubMed: 11032443).