Some properties of the main protein of honeybee (Apis mellifera) royal jelly

Royal jelly (RJ) was separated by ultracentrifugation (245000 $\times$ g for 5 h at 6 oC) into three physically distinct fractions with different distribution of its components (proteins, sugars and fatty acids): yellowish fluid supernatant (61% w/w of RJ), yellowish-brown gelatinous sediment (32% w/w) and white nearly solid sediment (7% , w/w). Ultracentrifugation of the solvated gelatinous fraction was a suitable method for preparation of MRJP1, the most abundant protein of RJ in the form of gel. MRJP1 was present in RJ in different forms: a monomer (55 kDa), oligomeric subunit (ca. 420 kDa), and water-insoluble aggregates in sediment after its interaction with fatty acids. The oligomeric MRJP1 was well soluble in water and at concentrations of 30 to 50% (w/w) formed a stiff gel. It is suggested that MRJP1 is albumin-like protein. An interesting feature of the oligomeric form of MRJP1 is its ability for self-assembly in water solutions

Isolation of a peptide fraction from honeybee royal jelly as a potential antifoulbrood factor

A peptide fraction was isolated from honeybee royal jelly (RJ) using dual dialysis under acidic conditions. The N-terminal amino acid sequence of the major peptide within the fraction was V-T-C-D-L-L-S-F-K-G. This sequence corresponds to the honeybee defensin royalisin of MW 5523 Da which has been shown to exert antibacterial activity against some Gram-positive bacteria. Diffusion tests on agar plates showed that the peptide fraction had an inhibitory effect against the honeybee pathogen Paenibacillus larvae larvae, the primary pathogen of American foulbrood disease, as well as against other Gram-positive bacteria such as Bacillus subtilis and Sarcina lutea. Moreover, the peptide fraction was shown also to have antifungal effect against the model fungus Botrytis cinerea. It is the first evidence of an antibiotic effect of royalisin against a honeybee pathogen. The procedure described is very simple and does not require application of complicated separation techniques. It is based on dialysis of RJ using membranes with different pore sizes, which enable to separate the compounds having molecular weight below 2 kDa, between 2 kDa and 10 kDa, and over 10 kDa

New approach to the study of division of labour in the honeybee colony (Apis mellifera L)

Using Northern analysis we determined differences in the transcription level of 4 mRNAs (coding for larval food proteins) in the heads of sister worker bees, which were either foragers or nurses rearing the larvae of workers, drones and queens. The ratio of the isolated total RNAs from the heads of these bee samples was estimated as 1:2:1.9:3.6, respectively

Identification of honeybee peptide active against Paenibacillus larvae larvae through bacterial growth-inhibition assay on polyacrylamide gel

The inhibition bands showing activity against Gram-positive bacteria were detected by analyses of acidic extracts of honeybee heads, thoraxes, and royal jellies (RJs) using a bacterial growth-inhibition assay on polyacrylamide gel. The presence of antibacterial peptide royalisin and another unknown peptide was found in two detected RJ inhibition bands by N-terminal sequencing. The data suggested that royalisin was the peptide responsible for the activity against Paenibacillus larvae larvae and other tested Gram-positive bacteria. The analyses of RJs collected from individual colonies at two apiaries, one of which showed incidence of American foulbrood, revealed differences in the content of the antibacterial peptide. The results suggest that the differences might be associated with genetic variability between colonies

Apisimin, a new serine–valine-rich peptide from honeybee (Apis mellifera L.) royal jelly: purification and molecular characterization11GeneBank accession number bankit 422221 AY055108 10-SEP-2001.

AbstractA peptide named apisimin was found in honeybee (Apis mellifera L.) royal jelly (RJ). N-terminal sequencing showed that this peptide corresponded to the sequence of a cDNA clone isolated from an expression cDNA library prepared from heads of nurse honeybees. No homology was found between the protein sequence of apisimin with a molecular mass of 5540.4 Da and sequences deposited in the Swiss-Prot database. The 54 amino acids of apisimin do not include Cys, Met, Pro, Arg, His, Tyr, and Trp residues. The peptide shows a well-defined secondary structure as observed by CD spectroscopy, and has the tendency to form oligomers. Isoelectrofocusing showed apisimin to be an acidic peptide

A simple, non-radioactive DNA fingerprinting method for identifying patrilines in honeybee colonies

Primers were derived flanking a microsatellite motif of the cloned Z-locus. The PCR product of the Z-locus was variable in size and up to four alleles were found in a sample of 11 workers within one colony. Using the combination of three loci, the Z, the Q (both linked to the sex locus) and a royal jelly protein gene (RJP57-1) we were able to discriminate five patrilines in the 11 worker sample. Using the well established microsatellite technology, however, seven and six patrilines could be identified. The technique may enable laboratories which lack an isotope facility and equipped with only a PCR thermocycler and agarose gel apparatus to study the polyandrous mating system of the honeybee in a variety of different contexts. © Inra/DIB/AGIB/Elsevier, Pari