The Foster method: Rapid and non-invasive detection of clinically relevant American Foulbrood disease levels using eDNA sampling and a dual-target qPCR assay, with its potential for other hive pathogens.

Clinical signs of American Foulbrood can be difficult to diagnose and thus disease is missed and leads to further spread. Diagnosis is centred on the beekeeper's skill in recognising clinical symptoms – a highly subjective and time-consuming activity. Previous testing methods have relied on sampling that necessitates dismantling the hive and/or requires multiple visits to retrieve passive samples. The Foster method is a new environmental DNA sampling method using entrance swabs together with a dual-target qPCR for AFB. The quantification data generated can be used to detect hives with clinically relevant infections, even when no visual symptoms are apparent. Such a method will be applicable to other bee pathogens and incursion pests.

Mechanistic Insight into Royal Protein Inhibiting the Gram-Positive Bacteria

Royal jelly (RJ), a natural honeybee product, has a wide range of antibacterial activities. N-glycosylated major royal jelly protein 2 (N-MRJP2), purified from RJ, can inhibit the growth of Paenibacillus larvae (P. larvae, Gram-positive), a contagious etiological agent of the American foulbrood disease of honeybees. However, the inhibitory mechanism is largely unknown. Antibacterial assay and membrane proteome were conducted to investigate the inhibition capacity of RJ from different instar larvae and P. larvae treated by N-MRJP2, respectively. The similar antibacterial efficiency of RJ from different larval instar indicates that RJ is vital for the adaptive immune defense of small larvae. The killing of P. larvae by N-MRJP2 is achieved by disturbing the cell wall biosynthesis, increasing the permeability of cell membrane, hindering aerobic respiration, restraining cell division and inducing cell death. This demonstrates that RJ is critical for the passive immunity of immature larvae and N-MRJP2 can be used as natural antibiotic substance to resist P. larvae, even for other gram-positive bacteria. This constitutes solid evidence that RJ and N-MRJP2 have potentials as novel antibacterial agents.

Actinobacteria associated with stingless bees biosynthesize bioactive polyketides against bacterial pathogens

Strong activity against the bacteria Paenibacillus larvae ATCC9545, the causative agent of the American Foulbrood disease of honey bees.

Complete Genome Sequences of Paenibacillus larvae Phages Halcyone, Heath, Scottie, and Unity from Las Vegas, Nevada

We present the complete genome sequences of four phages that infect Paenibacillus larvae, the causative agent of American foulbrood disease in honeybees. The phages were isolated from beehives and beeswax products from Las Vegas, Nevada.

Using palynological evidence from royal jelly to mediate the spread of Paenibacillus larvae in Brazil

ABSTRACT Royal jelly may contain pollen grains and their presence can be used to determine the phytogeographical origin of the product. This study analyzed the phytogeographical origin of commercial royal jelly samples from São Paulo State, tested as part of the Brazilian Federal Inspection System (SIF), found to be contaminated with spores of the bacterium Paenibacillus larvae, that causes the American Foulbrood Disease. The pollen grains of Castanea had the highest total percentage, with lower percentages of Cirsium/Carduus, Cistus, Parthenocissus, Prunus, Quercus, Robinia, Scrophulariaceae, Taraxacum, Tilia, among others. This pollen spectrum is incompatible with royal jelly samples produced in Brazil. The pollen spectrum resembled that of an imported product, compatible with the Northern Hemisphere origin. Brazilian legislation does not require the phytogeographic origin of imported bee products to be analyzed by palynological procedures, but it is mandatory to have a certificate issued by the country of origin attesting the absence of pathogens, monitored with the objective of preventing the exotic diseases from entering Brazil. Palynology, therefore, proved to be fundamental in detecting imports of this contaminated batches.