INVESTIGADORES
BERON Corina Marta
congresos y reuniones científicas
Título:
MOLECULAR CHARACTERIZATION OF cry GENES PRESENT IN A Bacillus thuringiensis STRAIN TOXIC AGAINST Aedes aegypti LARVAE
Autor/es:
MARÍA EMILIA VIDAL DOMÍNGUEZ; CORINA BERÓN
Lugar:
Villa Carlos Paz, Argentina
Reunión:
Congreso; VI Congreso Argentino de Microbiología General; 2009
Institución organizadora:
Sociedad Argentina de Microbiología General
Resumen:
<!-- /* Font Definitions */ @font-face {font-family:Calibri; panose-1:0 0 0 0 0 0 0 0 0 0; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-format:other; mso-font-pitch:auto; mso-font-signature:3 0 0 0 1 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:ES-AR; mso-fareast-language:ES; mso-no-proof:yes;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> The mosquito Aedes aegypti, vector of the dengue and yellow fiber viruses, is found in nearly 100 countries worldwide. Current program strategies for the control of dengue and yellow fever have a small impact on the mosquito and are in critical need for a comprehensive, aggressive revamping. The World Health Organization makes special emphasis in the integrated epidemiological and entomological surveillance of the mosquito’s population. Bacillus thuringiensis comprises a group of aerobic, spore-forming bacteria that produce a toxic crystalline inclusion, delta-endotoxin, or Cry protein, lethal to various insect orders. Although insecticidal proteins from B. thuringiensis have been used as spray against A. aegypti for the past 20 years, a significant number of desease carrying mosquitos are not affected by the available Cry proteins. Therefore, it is necessary to search for proteins with wider and/or specific toxic spectrum. Additionally, it is important to provide alternatives for coping with the problem of insect resistance that has already appeared against some of the formulates. Recently, we have isolated a new mosquitocidal B. thuringiensis strain (FCC 41) native to Argentina. This isolate was partially charaterized as showing higher mosquitocidal effect than the strain B. thuringiensis israelensis (HD 567). Described in a previous work, the polypeptide pattern of purified parasporal bodies analyzed by SDS-PAGE, showed two major polypeptides of about Mr 70 - 80 kDa, and the cry gene sequence named Cry24Ca was isolated. In the present work, a method was used based on PCR-RFLP and Denaturing Gradient Gel Electrophoresis (DGGE) profiling and sequencing of the highly variable cry gene to characterize gene contents from B. thuringiensis strains. By these methods we found three parcial aminoacid sequences that showed identities of about 90 - 95% or less with the Cry24Ca protein previously described.