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Licensed Unlicensed Requires Authentication Published by De Gruyter July 29, 2016

Characterization of a new toxin from the entomopathogenic fungus Metarhizium anisopliae: the ribotoxin anisoplin

  • Miriam Olombrada ORCID logo , Pilar Medina , Flor Budia , José G. Gavilanes , Álvaro Martínez-del-Pozo and Lucía García-Ortega EMAIL logo
From the journal Biological Chemistry


Metarhizium anisopliae is an entomopathogenic fungus relevant in biotechnology with applications like malaria vector control. Studies of its virulence factors are therefore of great interest. Fungal ribotoxins are toxic ribonucleases with extraordinary efficiency against ribosomes and suggested as potential insecticides. Here we describe this ribotoxin characteristic activity in M. anisopliae cultures. Anisoplin has been obtained as a recombinant protein and further characterized. It is structurally similar to hirsutellin A, the ribotoxin from the entomopathogen Hirsutella thompsonii. Moreover, anisoplin shows the ribonucleolytic activity typical of ribotoxins and cytotoxicity against insect cells. How Metarhizium uses this toxin and possible applications are of interest.


This work was supported by projects BFU2012-32404 and AGL2010-22196-C02-02 from the Spanish Ministerio de Economía y Competitividad, and ESFUNPROT-UCM from Universidad Complutense de Madrid. Miriam Olombrada is recipient of a FPU predoctoral fellowship from the Spanish Ministerio de Educación. Lucía García-Ortega is a researcher of the PICATA program from the Campus de Excelencia Internacional Moncloa.


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Supplemental Material:

The online version of this article (DOI: 10.1515/hsz-2016-0119) offers supplementary material, available to authorized users.

Received: 2016-1-21
Accepted: 2016-7-21
Published Online: 2016-7-29
Published in Print: 2017-1-1

©2017 Walter de Gruyter GmbH, Berlin/Boston

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