Photorhabdus virulence cassettes confer injectable insecticidal activity against the wax moth
Yang, G., Dowling, A. J., Gerike, U., ffrench-Constant, R. H. and Waterfield, N. R., 2006. Photorhabdus virulence cassettes confer injectable insecticidal activity against the wax moth. Journal of Bacteriology, 188 (6), pp. 2254-2261.
Related documents:This repository does not currently have the full-text of this item.
You may be able to access a copy if URLs are provided below.
Two recently sequenced genomes of the insect-pathogenic bacterium Photorhabdus and a large Serratia entomophila plasmid, pADAP, have phage-related loci containing putative toxin effector genes, designated the "Photorhabdus virulence cassettes" (PVCs). In S. entomophila, the single plasmid PVC confers antifeeding activity on larvae of a beetle. Here, we show that recombinant Escherichia coli expressing PVC-containing cosmids from Photorhabdus has injectable insecticidal activity against larvae of the wax moth. Electron microscopy showed that the structure of the PVC products is similar to the structure of the antibacterial R-type pyocins. However, unlike these bacteriocins, the PVC products of Photorhabdus have no demonstrable antibacterial activity. Instead, injection of Photorhabdus PVC products destroys insect hemocytes, which undergo dramatic actin cytoskeleton condensation. Comparison of the genomic organizations of several PVCs showed that they have a conserved phage-like structure with a variable number of putative anti-insect effectors encoded at one end. Expression of these putative effectors directly inside cultured cells showed that they are capable of rearranging the actin cytoskeleton. Together, these data show that the PVCs are functional homologs of the S. entomophila antifeeding genes and encode physical structures that resemble bacteriocins. This raises the interesting hypothesis that the PVC products are bacteriocin-like but that they have been modified to attack eukaryotic host cells.
|Creators||Yang, G., Dowling, A. J., Gerike, U., ffrench-Constant, R. H. and Waterfield, N. R.|
|Departments||Faculty of Science > Biology & Biochemistry|
Actions (login required)