title: Urease from cotton (Gossypium hirsutum) seeds: isolation, physicochemical characterization, and antifungal properties of the protein.
abstract: Ureases (EC 3.5.1.5) are metalloenzymes that hydrolyze urea to produce ammonia and carbon dioxide These enzymes, which are found in fungi, bacteria, and plants, show very similar structures. Despite an abundance of urease in vegetal tissues, the physiological role of this enzyme in plants is still poorly understood. It has been previously described that ureases from the legumes jackbean ( Canavalia ensiformis) and soybean ( Glycine max) have insecticidal activity and antifungal properties. This work presents the physicochemical purification and characterization of a urease from cotton ( Gossypium hirsutum) seeds, the first description of this enzyme in Malvaceae. The urease content varied among different cotton cultivars. Cotton seed urease (98.3 kDa) displayed low ureolytic activity but exhibited potent antifungal properties at sub-micromolar concentrations against different phytopathogenic fungi. As described for other ureases, the antifungal effect of cotton urease persisted after treatment with an irreversible inhibitor of its enzyme activity. The data suggest an important role of these proteins in plant defense.
authors.affiliation: Graduate Program in Molecular and Cellular Biology-Center of Biotechnology and Department of Biophysics, Universidade Federal do Rio Grande do Sul-UFRGS, Porto Alegre, RS CEP 91501-970, Brazil.
authors.forename: Angela
authors.initials: A
authors.lastname: Menegassi
authors.forename: German E
authors.initials: GE
authors.lastname: Wassermann
authors.forename: Deiber
authors.initials: D
authors.lastname: Olivera-Severo
authors.forename: Arlete B
authors.initials: AB
authors.lastname: Becker-Ritt
authors.forename: Anne Helene S
authors.initials: AH
authors.lastname: Martinelli
authors.forename: Vanessa
authors.initials: V
authors.lastname: Feder
authors.forename: Celia R
authors.initials: CR
authors.lastname: Carlini
mesh_terms: D000595:Amino Acid Sequence; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D005659:Fungicides, Industrial / Q000494:pharmacology*; D003368:Gossypium / Q000201:enzymology*; D007700:Kinetics; D008969:Molecular Sequence Data; D012639:Seeds / Q000201:enzymology*; D014510:Urease / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*
chemical_list: D005659:Fungicides, Industrial; D014510:Urease