Antagonistic effect of gut microbiota of honeybee (apis mellifera) against causative agent of american foulbrood paenibacillus larvae

and to identify their anti-Paenibacillus larvae affect. In our study, 200 samples of bee’s gut originated from honeybee of Slovak origin
were tested. A total of 23 species of 17 bacterial genera (10 Gram-negative and 6 Gram-positive, one yeast) were identified in gut of
bees with MALDI-TOF Mass Spectrometry. The bacterial strains Bacillus cereus, B. megatherium, B. oleronius, B. thuringiensis,
Delftia acidovorans, Escherichia coli, Enterococcus cloacae, Issatchenkia orientalis, Klebsiella oxytoca, Lactobacillus acidophilus, L.
crispatus, L. kunei, Morganella morgani, Pantotea aglomerans, P. ananatis, Pseudomonas oryzihabitans, Rahnella aquatilis, R.
terrigena, Raoutella ornithinolytica, Serratia liquefaciens, S. marcescens, Sphingomonas parapaucimobilis, Staphylococcus epidermidis
were representative part of gut microflora of bees. Bees isolates of Paenibacillus larvae and Paenibacillus larvae CCM 4438 were
tested for antimicrobial activity. The best antimicrobial activity against P. larvae isolated from bee’s gut showed L. kunkei, L. crispatus
and L. acidophilus. The lower antibacterial activity against P. larvae was found in Raoutella ornithinolytica, Pantotea ananatis and
Serratia liquefaciens isolated from bees’ gut. The strongest antimicrobial activity of L. kunkei, L. acidophilus and L. crispatus and the
lowest antimicrobial activity of Pantotea ananatis and Rahnella aquatilis were found against P. larvae CCM 4438.