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 Link
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: 10.1016/j.jip.2014.07.001
