Title: Molecular analysis of a novel gene cluster encoding an insect toxin in plant-associated strains of Pseudomonas fluorescens
Authors : Péchy-Tarr, M.
Bruck, D. J.
Maurhofer, M.
Fischer, Esther
Vogne, C.
Henkels, M. D.
Donahue, K. M.
Grunder, Jürg
Loper, J. E.
Keel, C.
Published in : Environmental Microbiology
Volume(Issue) : 10
Issue : 9
Pages : 2368
Pages to: 2386
Publisher / Ed. Institution : Wiley
Issue Date: 2008
License (according to publishing contract) : Licence according to publishing contract
Type of review: Peer review (Publication)
Language : English
Subjects : Phytopathology; Bacterial toxin
Subject (DDC) : 630: Agriculture
Abstract: Pseudomonas fluorescens CHA0 and the related strain Pf-5 are well-characterized representatives of rhizosphere bacteria that have the capacity to protect crop plants from fungal root diseases, mainly by releasing a variety of exoproducts that are toxic to plant pathogenic fungi. Here, we report that the two plant-beneficial pseudomonads also exhibit potent insecticidal activity. Anti-insect activity is linked to a novel genomic locus encoding a large protein toxin termed Fit (for P. fluorescensinsecticidal toxin) that is related to the insect toxin Mcf (Makes caterpillars floppy) of the entomopathogen Photorhabdus luminescens, a mutualist of insect-invading nematodes. When injected into the haemocoel, even low doses of P. fluorescens CHA0 or Pf-5 killed larvae of the tobacco hornworm Manduca sexta and the greater wax moth Galleria mellonella. In contrast, mutants of CHA0 or Pf-5 with deletions in the Fit toxin gene were significantly less virulent to the larvae. When expressed from an inducible promoter in a non-toxic Escherichia coli host, the Fit toxin gene was sufficient to render the bacterium toxic to both insect hosts. Our findings establish the Fit gene products of P. fluorescens CHA0 and Pf-5 as potent insect toxins that define previously unappreciated anti-insect properties of these plant-colonizing bacteria.
Departement: Life Sciences und Facility Management
Organisational Unit: Institute of Natural Resource Sciences (IUNR)
Publication type: Article in scientific Journal
DOI : 10.1111/j.1462-2920.2008.01662.x
ISSN: 1462-2920
URI: https://digitalcollection.zhaw.ch/handle/11475/7568
Appears in Collections:Publikationen Life Sciences und Facility Management

Files in This Item:
There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.