title: Evaluation of the potential allergenicity of the enzyme microbial transglutaminase using the 2001 FAO/WHO Decision Tree.
abstract: All novel proteins must be assessed for their potential allergenicity before they are introduced into the food market. One method to achieve this is the 2001 FAO/WHO Decision Tree recommended for evaluation of proteins from genetically modified organisms (GMOs). It was the aim of this study to investigate the allergenicity of microbial transglutaminase (m-TG) from Streptoverticillium mobaraense. Amino acid sequence similarity to known allergens, pepsin resistance, and detection of protein binding to specific serum immunoglobulin E (IgE) (RAST) have been evaluated as recommended by the decision tree. Allergenicity in the source material was thought unlikely, since no IgE-mediated allergy to any bacteria has been reported. m-TG is fully degraded after 5 min of pepsin treatment. A database search showed that the enzyme has no homology with known allergens, down to a match of six contiguous amino acids, which meets the requirements of the decision tree. However, there is a match at the five contiguous amino acid level to the major codfish allergen Gad c1. The potential cross reactivity between m-TG and Gad c1 was investigated in RAST using sera from 25 documented cod-allergic patients and an extract of raw codfish. No binding between patient IgE and m-TG was observed. It can be concluded that no safety concerns with regard to the allergenic potential of m-TG were identified.
authors.affiliation: Laboratory of Medical Allergology, Allergy Clinic, National University Hospital, Copenhagen, Denmark.
authors.forename: Mona H
authors.initials: MH
authors.lastname: Pedersen
authors.forename: Tine K
authors.initials: TK
authors.lastname: Hansen
authors.forename: Eva
authors.initials: E
authors.lastname: Sten
authors.forename: Katsuya
authors.initials: K
authors.lastname: Seguro
authors.forename: Tomoko
authors.initials: T
authors.lastname: Ohtsuka
authors.forename: Akiko
authors.initials: A
authors.lastname: Morita
authors.forename: Carsten
authors.initials: C
authors.lastname: Bindslev-Jensen
authors.forename: Lars K
authors.initials: LK
authors.lastname: Poulsen
mesh_terms: D000818:Animals; D003257:Consumer Product Safety; D003429:Cross Reactions; D003663:Decision Trees; D005512:Food Hypersensitivity / Q000517:prevention & control*; D048389:Gadus morhua / Q000276:immunology; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D007073:Immunoglobulin E / Q000096:biosynthesis / Q000276:immunology; D030781:Organisms, Genetically Modified; D010434:Pepsin A / Q000378:metabolism; D018570:Risk Assessment; D017386:Sequence Homology, Amino Acid; D013302:Streptomyces / Q000201:enzymology; D011503:Transglutaminases / Q000737:chemistry / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D014357:Trypsin / Q000378:metabolism
chemical_list: D007106:Immune Sera; D007073:Immunoglobulin E; D011503:Transglutaminases; D014357:Trypsin; D010434:Pepsin A