title: Interaction between wheat alpha-amylase/trypsin bi-functional inhibitor and mammalian digestive enzymes: Kinetic, equilibrium and structural characterization of binding.
abstract: Alpha-amylase/trypsin bi-functional inhibitors (ATIs) are non-gluten protein components of wheat and other cereals that can hypersensitise the human gastrointestinal tract, eventually causing enteropathies in predisposed individuals. These inhibitory proteins can act both directly by targeting specific pro-inflammatory receptors, and indirectly by impairing the activity of digestive enzymes, the latter event causing the accumulation of undigested peptides with potential immunogenic properties. Herein, according to a concerted approach based on in vitro and in silico methods we characterized kinetics, equilibrium parameters and modes of binding of the complexes formed between wheat ATI and two representative mammalian digestive enzymes, namely trypsin and alpha-amylase. Interestingly, we demonstrated ATI to target both enzymes with independent binding sites and with moderately high affinity.
authors.affiliation: School of Biosciences and Veterinary Medicine, Via Gentile III da Varano, 62032 Camerino (MC), Italy. Electronic address: massimiliano.cuccioloni@unicam.it.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Cuccioloni
authors.affiliation: School of Biosciences and Veterinary Medicine, Via Gentile III da Varano, 62032 Camerino (MC), Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Mozzicafreddo
authors.affiliation: School of Biosciences and Veterinary Medicine, Via Gentile III da Varano, 62032 Camerino (MC), Italy.
authors.forename: Ishtiaq
authors.initials: I
authors.lastname: Ali
authors.affiliation: School of Biosciences and Veterinary Medicine, Via Gentile III da Varano, 62032 Camerino (MC), Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Bonfili
authors.affiliation: School of Biosciences and Veterinary Medicine, Via Gentile III da Varano, 62032 Camerino (MC), Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Cecarini
authors.affiliation: School of Biosciences and Veterinary Medicine, Via Gentile III da Varano, 62032 Camerino (MC), Italy.
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Eleuteri
authors.affiliation: School of Biosciences and Veterinary Medicine, Via Gentile III da Varano, 62032 Camerino (MC), Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Angeletti
mesh_terms: D000818:Animals; D001665:Binding Sites; D002523:Edible Grain / Q000737:chemistry; D006801:Humans; D059748:Proteolysis; D013816:Thermodynamics; D014908:Triticum / Q000737:chemistry*; D014361:Trypsin Inhibitors / Q000737:chemistry*; D000516:alpha-Amylases / Q000037:antagonists & inhibitors*
chemical_list: D014361:Trypsin Inhibitors; D000516:alpha-Amylases
keywords: Bifunctional inhibitor; Binding mode; Gluten sensitivity; Kinetics; Thermodynamics; Wheat