AF141: Potato inhibitor I family

List allergens from this family:

Routes of exposure:
Include only IUIS approved allergens.

Biochemical properties

These serine protease inhibitors inhibit proteases from the chymotrysin (S1) and subtilisin (S8) families. These inhibitors are small (60 to 90 residues) and, in contrast with other families of protease inhibitors, they lack disulfide bonds. Members of this family are found in potatoes and wide range of other plant species. This family is classified among the plant pathogenesis-related proteins as family PR-6 [1].

Allergens from this family

A protease inhibitor from wheat was identified as a minor wheat allergen for patients with baker's asthma, but not for patients with wheat-induced food allergy [2].



  1. van Loon LC, Rep M, Pieterse CM:
    Significance of inducible defense-related proteins in infected plants.
    Annu Rev Phytopathol 2006, 44, 135-62. [PubMed] [Full Text]
  2. Constantin C, Quirce S, Grote M, Touraev A, Swoboda I, Stoecklinger A, Mari A, Thalhamer J, Heberle-Bors E, Valenta R:
    Molecular and immunological characterization of a wheat serine proteinase inhibitor as a novel allergen in baker's asthma.
    J Immunol 2008, 180, 7451-60. [PubMed]


Links to Pfam

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

Pfam domain Pfam clan
PF00280 Potato inhibitor I family CL0367 CI-2 family of serine protease inhibitors


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