Interaction of jack bean (Canavalia ensiformis) urease and a derived peptide with lipid vesicles.
Ureases are metalloenzymes that catalyze the hydrolysis of urea to ammonia and carbon dioxide. Jack bean (Canavalia ensiformis) produces three isoforms of urease (Canatoxin, JBU and JBURE-II). Canatoxin and JBU display several biological properties independent of their ureolytic activity, such as neurotoxicity, exocytosis-inducing and pro-inflammatory effects, blood platelets activation, insecticidal and antifungal activities. The Canatoxin entomotoxic activity is mostly due to an internal peptide, named pepcanatox, released upon the hydrolysis of the protein by insect cathepsin-like digestive enzymes. Based on pepcanatox sequence, Jaburetox-2Ec was produced in Escherichia coli. JBU and its peptides were shown to permeabilize membranes through an ion channel-based mechanism. Here we studied the JBU and Jaburetox-2Ec interaction with platelet-like multilamellar liposomes (PML) using Dynamic Light Scattering and Small Angle X-ray Scattering techniques. We also analyzed the interaction of JBU with giant unilamellar vesicles (GUVs) using Fluorescence Microscopy. The interaction of vesicles with JBU led to a slight reduction of hydrodynamic radius, and caused an increase in the lamellar repeat distance of PML, suggesting a membrane disordering effect. In contrast, Jaburetox-2Ec decreased the lamellar repeat distance of PML membranes, while also diminishing their hydrodynamic radius. Fluorescence microscopy showed that the interaction of GUVs with JBU caused membrane perturbation with formation of tethers. In conclusion, JBU can interact with PML, probably by inserting its Jaburetox "domain" into the PML external membrane. Additionally, the interaction of Jaburetox-2Ec affects the vesicle's internal bilayers and hence causes more drastic changes in the PML membrane organization in comparison with JBU.
Graduate Program in Chemistry, Institute of Chemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Yasmine Miguel Serafini
YMS
Micheletto
Graduate Program in Cellular and Molecular Biology, Center of Biotechnology, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Carlo Frederico
CF
Moro
Instituto do Cérebro, Pontíficia Universidade Católicado Rio Grande do Sul, Porto Alegre, RS, Brazil; Department of Biophysics, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Fernanda Cortez
FC
Lopes
Graduate Program in Cellular and Molecular Biology, Center of Biotechnology, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Rodrigo
R
Ligabue-Braun
Department of Biophysics, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Anne Helene Souza
AHS
Martinelli
Institut Charles Sadron, Université de Strasbourg, UPR22-CNRS, Strasbourg, France.
Carlos Manuel
CM
Marques
Institut Charles Sadron, Université de Strasbourg, UPR22-CNRS, Strasbourg, France.
André Pierre
AP
Schroder
Graduate Program in Cellular and Molecular Biology, Center of Biotechnology, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Instituto do Cérebro, Pontíficia Universidade Católicado Rio Grande do Sul, Porto Alegre, RS, Brazil; Department of Biophysics, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. Electronic address: celia.carlini@pucrs.br.
Célia Regina
CR
Carlini
Graduate Program in Chemistry, Institute of Chemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. Electronic address: nadya@iq.ufrgs.br.
Nádya Pesce
NP
da Silveira
D032449:Canavalia / Q000201:enzymology*; D000067493:Dynamic Light Scattering; D008081:Liposomes / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D010455:Peptides / Q000378:metabolism*; D053838:Scattering, Small Angle; D014510:Urease / Q000378:metabolism*; D014961:X-Ray Diffraction
D008081:Liposomes; D010455:Peptides; D014510:Urease
Jaburetox-2Ec; Jack bean urease; Light scattering; Liposomes; SAXS