Function of Urease in Plants with Reference to Legumes: A Review

Abstract

Urease (urea amidohydrolase, EC 3.5.1.5) is a nickel-containing enzyme produced by plants, fungi, and bacteria that catalyzes the hydrolysis of urea into ammonia and carbamate. Plant (especially legumes) ureases hold a special place in science history, participating on some important landmarks of biochemistry as it was the first enzyme ever to be crystallized in 1926. Finding nickel in urease’s active site in 1975 was the first indication of a biological role for this metal. Despite the abundance of urease in tissues and seeds of some members of Legumes families, and its ubiquity in virtually all plants little has been revealed of the roles of urease. This review will explore many faces of these ureases from legumes and other plants, their roles, nutritional relationship between plants and the commensal bacteria with which they associate. In addition, we will explore the possibility that bacteria participate in turnover of the “plant” urea pool. Plant ureases possess insecticidal and fungitoxic properties independent of its ureolytic activity. Altogether, with this review we wanted to invite the readers to take a second look at ureases from versatile plants especially legumes for various biotechnological applications.