AF059: Plant defensin

List allergens from this family:

Routes of exposure:
Include only IUIS approved allergens.

Biochemical properties

Plant defensins (also called γ-thionins) consist of a globular domain of 45-50 amino acids in length containing four conserved disulfide bonds. Some family members also contain a C-terminal unstructured, hydroxyproline-rich domain. The structure of the N-terminal domain differs from that of plant α- and β-thionins, but is similar to the structures of scorpion toxins and insect defensins. The peanut allergens Ara h 12 and Ara h 13 also belong to this family [1].

Allergens from this family

This family contains the major mugwort pollen allergen, Art v 1 [2] and its ragweed homologue, Amb a 4 [3]. The C-terminal domain contains many hydroxyproline residues that are modified by unusual O-glycans, which take part in IgE binding [4].



  1. Petersen A, Kull S, Rennert S, Becker WM, Krause S, Ernst M, Gutsmann T, Bauer J, Lindner B, Jappe U:
    Peanut defensins: Novel allergens isolated from lipophilic peanut extract.
    J Allergy Clin Immunol 2015, 136, 1295-301 e1-5. [PubMed] [Full Text]
  2. Himly M, Jahn-Schmid B, Dedic A, Kelemen P, Wopfner N, Altmann F, van Ree R, Briza P, Richter K, Ebner C, Ferreira F:
    Art v 1, the major allergen of mugwort pollen, is a modular glycoprotein with a defensin-like and a hydroxyproline-rich domain.
    FASEB J 2003, 17, 106-8. [PubMed] [Full Text]
  3. Leonard R, Wopfner N, Pabst M, Stadlmann J, Petersen BO, Duus JO, Himly M, Radauer C, Gadermaier G, Razzazi-Fazeli E, Ferreira F, Altmann F:
    A new allergen from ragweed (Ambrosia artemisiifolia) with homology to art v 1 from mugwort.
    J Biol Chem 2010, 285, 27192-200. [PubMed] [Full Text]
  4. Leonard R, Petersen BO, Himly M, Kaar W, Wopfner N, Kolarich D, van Ree R, Ebner C, Duus JO, Ferreira F, Altmann F:
    Two novel types of O-glycans on the mugwort pollen allergen Art v 1 and their role in antibody binding.
    J Biol Chem 2005, 280, 7932-40. [PubMed] [Full Text]


Links to Pfam

Family-defining Pfam domains (at least one of these domains is present in each family member):

Pfam domain Pfam clan
PF00304 Gamma-thionin family CL0054 Scorpion toxin-like knottin superfamily

Links to Wikipedia


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