Bacillus thuringiensis is a Gram-positive, spore forming bacteria, that produces a parasporal crystals during the stationary phase of growth. It is a species of outstanding scientific interest due to its leading role in microbial pesticides industry. The main components of its parasporal inclusions: delta-endotoxins represent the most successful use of insect biological control agent to date. Bacillus thuringiensis discovered to science in 1911 is already a useful alternative to synthetic chemical pesticide application in agriculture. It is also a key source of genes for transgenic expression to provide pest resistance in plants. Production improvement and engineering of new pore-forming toxins are the main scopes of Bacillus thuringiensis industry science.

We investigated the other side of this insect-pesticide battle, examining model organism Galleria mellonella, which is a honey bee hive pest. In our study we observed the humoral immune-response of this lepidopteran to Bacillus thuringiensis subsp. kurstaki. Bacteria kills wax moth efficiently in dosage-dependent manner. We studied the appearance of antimicrobial activity in hemolymph from immune-stimulated larvae. Both antibacterial and antifungal activity increased within 7 hours after infection and decreased afterwards, resulting in animal death. We showed that infection triggers MAP kinases pathways. Activation of MAP-kinases routes, measured as double phosphorylation of ERK, p38 and JNK MAP kinases in fat body cells at the beginning of immune response was observed. This may point at their importance in immune process since the fat body plays the main role in humoral response.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/10798 must be provided.

1. Thermolysin – an inductor of Galleria mellonella immune response
2. Antimicrobial peptides of Galleria mellonella degraded in vitro and in vivo by Pseudomonas aeruginosa protease B
3. Signal transduction in yeast upon stress conditions
4. Protein kinase A activity in haemocytes of Galleria mellonella larvae upon immune challenge conditions