Abstract
The prtA gene from Photorhabdus luminescens encodes the virulence factor Protease A. When P. luminescens is injected into the hemocoel of insects by entomopathogenic nematodes, PrtA is a key component of pathogenicity thought to help degrade the immune system. The prtA gene was cloned and introduced on a plasmid into Bacillus thuringiensis. PrtA was shown to be actively expressed in vitro by cleavage of a specific Dabcyl-Edans heptapeptide substrate. There was no difference in the speed or level of mortality when spores and δ-endotoxins crystals of the transformed strain were fed to larvae of Pieris brassicae, as compared to the wild-type strain. When vegetative cells were injected into the hemocoel of larvae of Galleriamellonella, however, there was a significant increase in the rate and level of mortality over the wild type. The yield of B. thuringiensis per cadaver was a hundred-fold greater in the PrtA-secreting strain. The increased pathogenicity from intrahemocoelic infection may have been due to a greater ability to overcome the immune response of G. mellonella while other factors such as resident gut bacteria may have negated this advantage after oral dosage.
DOI
10.1016/j.jip.2014.07.001
Publication Date
2014-09-01
Publication Title
Journal of Invertebrate Pathology
Volume
121
Publisher
Elsevier BV
ISSN
0022-2011
Embargo Period
2024-11-22
First Page
85
Last Page
88
Recommended Citation
Bishop, A. (2014) 'Expression of prtA from Photorhabdus luminescens in Bacillus thuringiensis enhances mortality in lepidopteran larvae by sub-cutaneous but not oral infection', Journal of Invertebrate Pathology, 121, pp. 85-88. Elsevier BV: Available at: https://doi.org/10.1016/j.jip.2014.07.001
