Fire ants of the genus Solenopsis have spread over large parts of the temperate and tropical world from their original habitats in South and Central America. In the southeastern United States, the stings of imported fire ants are the most common cause of insect venom anaphylaxis. Fire ant venom consists of a mixture of very basic piperidine alkaloids and a small aqueous phase containing four major proteins. A single fire ant sting is sufficient to cause specific IgE antibody production, although it contains only 1–10 ng of protein. In some endemic areas, 30–50% of the population shows evidence of sensitization to fire ant venom, as revealed by the presence of serum-specific IgE antibodies and by skin testing. Four allergenic proteins have been isolated from Solenopsis invicta venom and characterized. Sol i 1 is a phospholipase A1B that is similar to those found in wasp venoms and belongs to the lipoprotein lipase family. Sol i 3 is a member of the antigen 5/pathogenesis-related protein family. Sol i 2 and Sol i 4 are members of a unique protein family. Sol i 2 is a covalent dimer composed of two identical monomers. Each monomer contains seven cysteines: six cysteines form three intramolecular disulfide bridges that stabilize the structure. Although all of the Sol 2 allergens show a high degree of immunological cross-reactivity among the species tested, there are some species-specific determinants in the Sol 2 family of allergens. This picture depicts the x-ray structure of Sol i 2 protein from fire ants, over an AI-generated background (PDB code: 2YGU)

#molecularart .. #ant ... #allergen ... #sol2 ... #xray ... #solenopsis

Structure rendered with @proteinimaging and depicted with @corelphotopaint