Sales, Maurício Pereira deGomes, Carlos Eduardo Maia2014-12-172012-04-202014-12-172004-12-20GOMES, Carlos Eduardo Maia. Purificação, caracterização e atividade bioinseticida de um inibidor de tripsina de sementes de Crotalaria pallida. 2004. 74 f. Dissertação (Mestrado em Bioquímica; Biologia Molecular) - Universidade Federal do Rio Grande do Norte, Natal, 2004.https://repositorio.ufrn.br/jspui/handle/123456789/12530A proteinaceous trypsin inhibitor was purified from Crotalaria pallida seeds by ammonium sulphate fractionation, affinity chromatography on immobilized Trypsin-Sepharose and TCA precipitation. The trypsin inhibitor, named ITC, had Mr of 32.5 kDa by SDS-PAGE and was composed by two subunits with 27.7 and 5.6 kDa linked by disulphide bridges, a typical characteristic of Kunitz-Inhibitor family. ITC was stable until 50°C, and at 100°C its residual activity was of about 60%. Also, ITC was stable at pHs 2 to 12. The inhibition of trypsin by ITC was non-competitive, with a Ki of 8,8 x 10-7M. ITC inhibits weakly other serine proteinases such as chymotrypsin and elastase. The inhibition of papain (44% of inhibition), a cysteine proteinase was an indicative of the bi-functionality of ITC. In vitro assays against digestive proteinases from several Lepdoptera, Diptera and Coleoptera pests were made. ITC inhibited in 100% digestive enzymes of Ceratitis capitata (fruit fly), Spodoptera frugiperda and Alabama argillacea, the last one being a cotton pest. It also inhibited in 74.4% Callosobruchus maculatus (bean weevil) digestive enzymes, a Coleoptera pest. ITC, when added in artificial diet models, affected weakly the development of C. capitata larvae and it had a WD50 of 2.65% to C. maculatus larvaeapplication/pdfAcesso AbertoProteínas - bioquímicaInibidores de tripsina - sementesAtividade biológica - enzimas digestivasCultura agrícola - nordesteBiossíntesemasterThesisCNPQ::CIENCIAS BIOLOGICAS::BIOQUIMICA