A. Guerchicoff et al., INTRODUCTION AND EXPRESSION OF AN ANTI-DIPTERAN TOXIN GENE FROM BACILLUS-THURINGIENSIS IN NODULATING RHIZOBIA, Cellular and molecular biology, 42(5), 1996, pp. 729-735
Rhizobium-based inoculants are widely used in leguminous crops. Improv
ed strains with dual functions (i.e, nitrogen fixing and insecticidal)
could be successfully applied to organic pest management. These could
also be used as seed protectants, reducing the use of chemical insect
icides. The cryIVB gene from B. thuringiensis israelensis coding for a
n anti-dipteran toxin was used as a model for expression. A highly sta
ble plasmid vector (pTR101) was chosen in order to carry out nodulatio
n experiments in the absence of selective pressure. Constructions were
introduced into Rhizobium fredii 191 and meliloti 1021, through tripa
rental matings with a helper plasmid. Expression was monitored by West
ern blotting of crude extracts using a specific antibody raised agains
t recombinant CryIVB protein. Although rearrangements leading to delet
ions were observed, an immunoreactive polypeptide was reproducibly det
ected in both Rhizobia. The presence of the recombinant plasmids did n
ot affect the nodulative capacity nor the growth of the inoculated pla
nts.