RESUMO
Mo-CBP3 is an antifungal protein produced by Moringa oleifera which has been investigated as potential candidate for developing transgenic crops. Before the use of novel proteins, food safety tests must be conducted. This work represents an early food safety assessment of Mo-CBP3, using the two-tiered approach proposed by ILSI. The history of safe use, mode of action and results for amino acid sequence homology using the full-length and short contiguous amino acids sequences indicate low risk associated to this protein. Mo-CBP3 isoforms presented a reasonable number of alignments (>35% identity) with allergens in a window of 80 amino acids. This protein was resistant to pepsin degradation up to 2 h, but it was susceptible to digestion using pancreatin. Many positive attributes were presented for Mo-CBP3. However, this protein showed high sequence homology with allergens and resistance to pepsin digestion that indicates that further hypothesis-based testing on its potential allergenicity must be done. Additionally, animal toxicity evaluations (e.g. acute and repeated dose oral exposure assays) must be performed to meet the mandatory requirements of several regulatory agencies. Finally, the approach adopted here exemplified the importance of performing an early risk assessment of candidate proteins for use in plant transformation programs.
Assuntos
Antígenos de Plantas/efeitos adversos , Proteínas Alimentares/efeitos adversos , Alimentos Geneticamente Modificados/efeitos adversos , Modelos Moleculares , Moringa oleifera/metabolismo , Proteínas de Plantas/efeitos adversos , Sementes/metabolismo , Alérgenos/efeitos adversos , Alérgenos/química , Alérgenos/genética , Alérgenos/metabolismo , Ração Animal/efeitos adversos , Ração Animal/microbiologia , Animais , Antígenos de Plantas/química , Antígenos de Plantas/genética , Antígenos de Plantas/metabolismo , Brasil , Quitina/metabolismo , Proteínas Alimentares/química , Proteínas Alimentares/metabolismo , Digestão , Hipersensibilidade Alimentar/etiologia , Hipersensibilidade Alimentar/prevenção & controle , Alimentos Geneticamente Modificados/microbiologia , Humanos , Ligantes , Fungos Mitospóricos/crescimento & desenvolvimento , Moringa oleifera/genética , Controle Biológico de Vetores/métodos , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/efeitos adversos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Isoformas de Proteínas/efeitos adversos , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Medição de Risco , Sementes/genética , Homologia de Sequência de AminoácidosRESUMO
The prevalence of fish allergy is rapidly increasing because of a growing fish consumption driven mainly by a positive image of the fish and health relationship. The purpose of this study was to characterize parvalbumin isotypes from grass carp (Ctenopharyngodon idella), one of the most frequently consumed freshwater fish in China. Three parvalbumin isotypes were purified using consecutive gel filtration and reverse-phase chromatography and denoted as PVI, PVII, and PVIII. The molecular weights of the isotypes were determined to be 11.968, 11.430, and 11.512 kDa, respectively. PVI showed 74% matched amino acids sequence with PV isotype 4a from Danio rerio, while PVII and PVIII showed 46% matched amino acids sequence with PV isotypes from Hypophthalmichthys molitrix. PVII is the dominant allergen, but it was liable to gastrointestinal enzymes as PVIII; however, PVI was resistant to pepsin digestion. A further study is to characterize the epitopes of PVII, the dominant allergen.