Apis mellifera (Honeybee) apisimin
May play an important role in honeybee nutrition. However, its role could not only be associated with larval development, because high level of mRNA is found in both forager and nurse honeybees (PubMed:12297291). No antimicrobial activity (tested on E.coli, B.subtilis or Paenibacillus l. larvae) has been observed (PubMed:12297291).
FEBS Lett. 2002 Sep 25;528(1-3):125-9. Apisimin, a new serine-valine-rich peptide from honeybee (Apis mellifera L.) royal jelly: purification and molecular characterization. Bíliková K1, Hanes J, Nordhoff E, Saenger W, Klaudiny J, Simúth J.
Abstract and paper
A 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.
Food Chemistry Volume 168, 1 February 2015, Pages 34-40. Honeybee apisimin and plant arabinogalactans in honey costimulate monocytes. Swapna Gannabathula, Geoffrey W. Krissansen, Margot Skinner, Gregor Steinhorn, Ralf Schlothauer
Here we determined whether immunostimulatory plant-derived arabinogalactan proteins (AGPs) and the honeybee-derived protein apisimin are present in varieties of New Zealand honey. Apisimin is a protein of unknown function secreted from the glands of honeybees into Royal Jelly, forming a complex with apalbumin1 capable of stimulating lymphocyte proliferation. AGPs were abundant in kanuka honey with lesser amounts in manuka, kowhai and clover honeys, but absent from Royal Jelly. Apisimin was present in all honeys, as well as Royal Jelly. We report that apisimin shares with honey AGPs the ability to stimulate the release of TNF-α from blood monocytes. Further, it synergizes with AGPs to enhance the release of TNF-α, via a mechanism not involving the formation of a complex with AGPs. In summary, this study provides evidence that AGPs and apisimin are commonly present in different floral varieties of honey, and hence contribute to their immunostimulatory properties.
1) Arabinogalactan proteins (AGPs) are present in different floral varieties of honey. 2) Honeybee-derived apisimin is present in all honeys examined at similar concentrations. 3) Apisimin stimulates the release of TNF-α from blood monocytes. 4) Apisimin synergizes with AGPs to enhance the release of TNF-α.
Besides their nutritional role, MRJP1 is a key factor responsible for honeybee development. Furthermore, MRJP1 plays important roles in bee brain functions such as learning, memory, and social behaviour. MRJP1 also exhibits a broad range of pharmacological activities in human health, such as promoting cell growth and wound healing, broad-spectrum antibacterial and antifungal activities, hypocholesterolemic effects, antitumor activity, vasodilative and anti-hypertension activity, and immune enhancement.