56 research outputs found
Crystallization and preliminary X-ray diffraction analysis of a novel trypsin inhibitor from seeds of Copaifera langsdorffii
A novel trypsin inhibitor isolated from seeds of Copaifera langsdorffii was purified to homogeneity and crystallized. Crystals suitable for X-ray analysis were grown using the hanging-drop vapour-diffusion method at 291 K in sodium acetate buffer at pH values near 4.3 using PEG 4000 as precipitant. The crystals presented symmetry compatible with the space group P4(1)2(1)2 or P4(3)2(1)2, with unit-cell parameters a = b = 58.71, c = 93.75 Angstrom, and diffracted to 1.83 Angstrom resolution at the synchrotron source.5791316131
Lima bean (Phaseolus lunatus) seed coat phaseolin is detrimental to the cowpea weevil (Callosobruchus maculatus)
Talisia esculenta lectin and larval development of Callosobruchus maculatus and Zabrotes subfasciatus (Coleoptera : Bruchidae)
Bruchid larvae cause major losses in grain legume crops throughout the world. Some bruchid species, such as the cowpea weevil and the Mexican bean weevil, are pests that damage stored seeds. Plant lectins have been implicated as antibiosis factors against insects, particularly the cowpea weevil, Callosobruchus maculatus. Talisia esculenta lectin (TEL) was tested for anti-insect activity against C. maculatus and Zabrotes subfasciatus larvae. TEL produced ca. 90% mortality to these bruchids when incorporated in an artificial diet at a level of 2% (w/w), The LD50 and FD50 for TEL was ca. 1% (w/w) for both insects. TEL was not digested by midgut preparations of C maculatus and Z, subfasciatus. The transformation of the genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops. (C) 2002 Elsevier Science B.V. All tights reserved.15712838
Properties of a Kunitz-Type Trypsin Inhibitor from Delonix regia Seeds Against Digestive Proteinases of Anagasta kuehniella (Z.) and Corcyra cephalonica (S.) (Lepidoptera: Pyralidae)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)DrTI was effective against trypsin-like enzymes from A. kuehniella and C. cephalonica, however an artificial diet was insufficient to affect the survival and body weight of either insect. The inhibitor stimulated chymotrypsin-like enzymes and probably induced the synthesis of enzymes insensitive to TLCK in neonate larvae.161214591465FUNDECT (Fundacao de Apoio ao Desenvolvimento do Ensino, Ciencia e Tecnologia do Estado de Mato Grosso do Sul)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FINEP (Financiamento de Estudos e Projetos/Ministerio da Ciencia e Tecnologia)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Biochemical characterization and N-terminal sequences of two new trypsin inhibitors from Copaifera langsdorffii seeds
Two new trypsin inhibitors, TDI-I and TDI-II, were purified from the seeds of the native Brazilian tree Copaifera langsdourfii (Caesalpinoideae, Leguminosae). The purification procedure involved ammonium sulfate fractionation, ion-exchange chromatography on DEAE-Sepharose, affinity chromatography on trypsin-Sepharose, and reversed-phase (RP) HPLC. RP-HPLC yielded two forms (TDI-I and TDI-II), as confirmed by isoelectric focusing, with pi values between 7.0 and 8.1. The molecular mass of the TDI forms was 24 kDa based on FPLC gel filtration on Superdex 75. Under reducing conditions in tricine SDS-PAGE the molecular masses of TDI-I and TDI-II were 12 and 10 kDa, respectively. The k(i) values were 1.1 and 1.2 nM for TDI-I and TDI-II, respectively, and there was no inhibitory effect on chymotrypsin. Amino acid analysis revealed high levels of aspartic acid, glutamic acid, serine, glycine, proline, and lysine but low levels of methionine and aromatic amino acids in both inhibitors; the calculated molecular masses were 11,456 and 10,008 for TDI-I and II, respectively. Eased on the N-terminal sequences of TDI-I and TDI-II, TDI-I belongs to the Kunitz family of trypsin inhibitors, whereas TDI-II showed no homology to any other protein. This observation suggests that TDI-II belongs to a new inhibitor subclass of low-molecular mass proteins in the subfamily Caesalpinoideae.2011
Characterization of a nonfimbrial mannose-sensitive hemagglutinin (MSH) produced by Salmonella enterica serovar Enteritidis
A nonfimbrial mannose-sensitive hemagglutinin (MSH) with adhesive properties produced by Salmonella enterica serovar Enteritidis was characterized. The MSH was characterized as glycoprotein and consisted of three noncovalently bound subunits of Mr 28, 33 and 40kDa determined by SDS-PAGE. The hemagglutinin was heat-stable and resistant to alkaline (high) or acid (low) pH, however, it was inhibited by proteolytic enzymes, by EDTA and by sodium periodate. Mouse antiserum raised against MSH reacted with the 28 kDa band in immunoblotting, and also inhibited hemagglutination and bacterial adherence to HeLa cells. Electron microscope examinations showed that MSH is not a fimbriae-like structure. MSH and anti-MSH IgG competitively inhibited bacterial adherence to HeLa cells. The immunofluorescence test, using MSH on HeLa cells and specific anti-MSH IgG, supported the view that MSH contributes to adherence of the organism. These results indicate that MSH is a nonfimbrial putative adhesive factor that may mediate the adherence of Salmonella enteritidis to eucaryotic cells. (c) 2006 Elsevier Ltd. All rights reserved.294179530131
Insecticidal Effect of Labramin, a Lectin—Like Protein Isolated from Seeds of the Beach Apricot Tree, Labramia bojeri
Influência do método de filetagem e categorias de peso sobre rendimento de carcaça, filé e pele da tilápia do Nilo (Oreochromis niloticus)
The objective of this study was to evaluate the processing methods (F-1 = to remove skin with pliers and then to cut in fillets; F-2 = cut in fillet and then to remove skin with knife and pliers help) and weight categories (W-1=250-300 g; W-2=301-350 g; W-3 = 351-400 g and W-4 = 401-450 g), on the carcass (CY), fillet (FY) and skin yield of Nile tilapia. Forty-eight fishes were used in a completely randomized design. There was effect for the processing method, being the F-1 mean (56.43 and 36.67 %) higher to the F-2 (53.46 and 32.89%) for CY and FY respectively. For the weight categories, W-1 (56.49 and 37.34%) and W-2 (56.34 and 36.40%) were superior as compared to W-3 (53.27 and 31.98%) and W-4 (53.71 and 33.42%), respectively for CY and FY. Crude skin percentage, clean and of fleshed were higher for F-2, but there was no effect for weight categories. The F-1 processing method promoted the best yield and skin results, and for the weight categories W-1 and W-2 higher yields
Trypsin inhibitor from Dimorphandra mollis seeds: purification and properties
A trypsin inhibitor from Dimorphandra mollis seeds was isolated to apparent homogeneity by a combination of ammonium sulfate precipitation, gel filtration, ion-exchange and affinity chromatographic techniques. SDS-PAGE analysis gave an apparent molecular weight of 20 kDa, and isoelectric focusing analysis demonstrated the presence of three isoforms. The partial N-terminal amino acid sequence of the purified protein showed a high degree of homology with various members of the Kunitz family of inhibitors. This inhibitor, which inhibited trypsin activity with a K-i of 5.3 x 10(-10) M, is formed by a single polypeptide chain with an arginine residue in the reactive site. (C) 2000 Elsevier Science Ltd. All rights reserved.54655355
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