Jelleines – a group of peptides with antimicrobial functions with potential anti-American foulbrood properties
1 Department of Biochemistry Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
2 Department of Protein Biochemistry and Proteomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
3 Department of Special Microbiology, State Veterinary Institute Olomouc, Jakoubka ze Střibra 1, 779 00 Olomouc, Czech Republic
Antimicrobial peptides are the important part of humoral immunity of animals. They occur across all organisms, including insects, where the largest number of antimicrobial peptides was isolated and characterized. This work is focused on the antimicrobial peptides present in royal jelly from honey bee (Apis mellifera), namely jelleine I and jelleine II. Jelleines are cleaved from the C-end of major royal jelly protein 1 (MRJP1).
We have been optimizing suitable protocols for exploring the antimicrobial activity of these peptides against various strains of Paenibacillus larvae, the causative agent of American foulbrood. A common diffusion assay revealed potential antimicrobial activities of jelleines against several strains of P. larvae. Several solutions were used for the dilution of synthetic peptides, e. g. water, MYPGP medium or 0.1% trifluoroacetic acid. Appropriate choice of diluting solution is the critical step to prevent losses of peptides on surfaces due to their high basicity. The diffusion assay does not permit to study the effect of peptides during incubation with bacteria and thus we tested luminescence or fluorescence-based assays for detailed description of anti-foulbrood activity of the peptides. These assays enable accurate quantification of live and dead cells which were incubated with antibacterial agents. This method presents opportunity to detect antimicrobial activities of jelleines and also to bring knowledge about their function in immune responses of honey bees to bacterial pathogens.