title: Practical and theoretical characterization of Inga laurina Kunitz inhibitor on the control of Homalinotus coriaceus.
abstract: Digestive endoprotease activities of the coconut palm weevil, Homalinotus coriaceus (Coleoptera: Curculionidae), were characterized based on the ability of gut extracts to hydrolyze specific synthetic substrates, optimal pH, and hydrolysis sensitivity to protease inhibitors. Trypsin-like proteinases were major enzymes for H. coriaceus, with minor activity by chymotrypsin proteinases. More importantly, gut proteinases of H. coriaceus were inhibited by trypsin inhibitor from Inga laurina seeds. In addition, a serine proteinase inhibitor from I. laurina seeds demonstrated significant reduction of growth of H. coriaceus larvae after feeding on inhibitor incorporated artificial diets. Dietary utilization experiments show that 0.05% I. laurina trypsin inhibitor, incorporated into an artificial diet, decreases the consumption rate and fecal production of H. coriaceus larvae. Dietary utilization experiments show that 0.05% I. laurina trypsin inhibitor, incorporated into an artificial diet, decreases the consumption rate and fecal production of H. coriaceus larvae. We have constructed a three-dimensional model of the trypsin inhibitor complexed with trypsin. The model was built based on its comparative homology with soybean trypsin inhibitor. Trypsin inhibitor of I. laurina shows structural features characteristic of the Kunitz type trypsin inhibitor. In summary, these findings contribute to the development of biotechnological tools such as transgenic plants with enhanced resistance to insect pests.
authors.affiliation: Departamento de Tecnologia de Alimentos, Centro de Ciências Biológicas e da Saúde, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil. bioplant@terra.com.br
authors.forename: Maria Lígia Rodrigues
authors.initials: ML
authors.lastname: Macedo
authors.forename: Maria das Graças Machado
authors.initials: Md
authors.lastname: Freire
authors.forename: Octávio Luiz
authors.initials: OL
authors.lastname: Franco
authors.forename: Ludovico
authors.initials: L
authors.lastname: Migliolo
authors.forename: Caio Fernando Ramalho
authors.initials: CF
authors.lastname: de Oliveira
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004064:Digestive System / Q000201:enzymology; D007887:Fabaceae; D019476:Insect Proteins / Q000302:isolation & purification / Q000494:pharmacology / Q000502:physiology*; D007814:Larva / Q000187:drug effects / Q000254:growth & development; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010447:Peptide Hydrolases / Q000502:physiology*; D010455:Peptides / Q000494:pharmacology*; D010940:Plant Proteins / Q000494:pharmacology*; D011480:Protease Inhibitors / Q000494:pharmacology; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D040681:Structural Homology, Protein; D048889:Weevils / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development
chemical_list: D019476:Insect Proteins; C053865:Kunitz-type protease inhibitor, plant; D010455:Peptides; D010940:Plant Proteins; D011480:Protease Inhibitors; D010447:Peptide Hydrolases