Chemical Modifications of Vicilins Interfere with Chitin-Binding Affinity and Toxicity to Callosobruchus maculatus (Coleoptera: Chrysomelidae) Insect: A Combined In Vitro and In Silico Analysis
| Autor: | Kayan Eudorico Ventury, Maria Raquel Alcântara de Miranda, Evenilton Pessoa Costa, Kátia Valevski Sales Fernandes, Adriana F. Uchoa, Olga L.T. Machado, Paulo R. L. Do Carmo, Sarah Rodrigues Ferreira, Antonia Elenir Amancio Oliveira |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
0106 biological sciences
chemistry.chemical_classification Chemistry In silico fungi 010401 analytical chemistry Lysine Tryptophan macromolecular substances General Chemistry 01 natural sciences 0104 chemical sciences Amino acid carbohydrates (lipids) chemistry.chemical_compound Biochemistry Chitin Acetylation Chitin binding Vicilin General Agricultural and Biological Sciences 010606 plant biology & botany |
| Zdroj: | Journal of Agricultural and Food Chemistry. 68:5596-5605 |
| ISSN: | 1520-5118 0021-8561 |
| Popis: | Vicilins are related to cowpea seed resistance toward Callosobruchus maculatus due to their ability to bind to chitinous structures lining larval midgut. However, this binding mechanism is not fully understood. Here, we identified chitin binding sites and investigated how in vitro and in silico chemical modifications interfere with vicilin chitin binding and insect toxicity. In vitro assays showed that unmodified vicilin strongly binds to chitin matrices, mainly with acetylated chitin. Chemical modifications of specific amino acids (tryptophan, lysine, tyrosine), as well as glutaraldehyde cross-linking, decreased the evaluated parameters. In silico analyses identified at least one chitin binding site in vicilin monomer, the region between Arg208 and Lys216, which bears the sequence REGIRELMK and forms an α helix, exposed in the 3D structure. In silico modifications of Lys223 (acetylated at its terminal nitrogen) and Trp316 (iodinated to 7-iodine-L-tryptophan or oxidized to β-oxy-indolylalanine) decreased vicilin chitin binding affinity. Glucose, sucrose, and N-acetylglucosamine also interfered with vicilin chitin binding affinity. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|