Characterization of nuclease activity produced and shedded by Trypanosoma cruzi trypomastigotes

DRAGO SOFÍA; GIANFRANCO ALI SANTORO; MARIA SUSANA LEGUIZAMON; JUAN BURGOS

Congreso; XXXI Reunión de la Sociedad Argentina deProtozoología; 2019

Characterization ofnuclease activity produced and shedded by Trypanosomacruzi trypomastigotesSofía Drago, Gianfranco Ali Santoro, M. SusanaLeguizamón, Juan M. BurgosIn severalpathogenic microorganisms, since bacteria to protozoos, production of nucleaseswas described as a virulence factor that, among other functions, would allowthem to escape from Neutrophil-produced NETs (neutrophil extracellular traps),DNA tramps produced as part of the natural immune response. Recently, Trypanosoma cruzi, the etiological agentof Chagas disease, was observed to induce NETs where, interestingly, parasitespersist alive.Herein wedescribe the production, shedding, and the first characterization of a nucleaseactivity by means of T. cruzi trypomastigotes(CL Brener strain). For these studies, cells-free parasites were incubated in CO2atmosphere from hours to several days and their supernatant was tested fornuclease activity. Through DNA degradation studies we observed that nuclease shedding,and its activity, depends on incubation temperature. Moreover, nuclease activitywas observed both on circular and lineal plasmid, as well as on human genomicDNA. By means of zymography approaches (SDS-PAGE with DNA from salmon testes),at least two proteins, of 40 and 55 kDa approximately, with nuclease activitywere observed. Among cofactors, activity depends on Mg++ presencebut not Ca++ cations, and is inhibited by Zn++ and EDTA.Moreover, it is no longer observed in samples heated above 70ºC. Ourobservations describe, by the first time, the production and shedding ofnuclease activity by T. cruzi trypomastigotes,which could constitute a new parasitic virulence factor. Protein purificationand identification is under process.<!-- /* Font Definitions */@font-face{font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1107305727 0 0 415 0;}@font-face{font-family:Calibri;panose-1:2 15 5 2 2 2 4 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1073786111 1 0 415 0;} /* Style Definitions */p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-unhide:no;mso-style-qformat:yes;mso-style-parent:"";margin-top:0cm;margin-right:0cm;margin-bottom:10.0pt;margin-left:0cm;line-height:115%;mso-pagination:widow-orphan;font-size:11.0pt;font-family:Calibri;mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:ES-AR;mso-fareast-language:EN-US;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-size:11.0pt;mso-ansi-font-size:11.0pt;mso-bidi-font-size:11.0pt;font-family:Calibri;mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:ES-AR;mso-fareast-language:EN-US;}.MsoPapDefault{mso-style-type:export-only;margin-bottom:8.0pt;line-height:107%;}size:595.3pt 841.9pt;margin:70.85pt 3.0cm 70.85pt 3.0cm;mso-header-margin:35.4pt;mso-footer-margin:35.4pt;mso-paper-source:0;}div.WordSection1{page:WordSection1;}