Purification and partial characterization of an aminopeptidase from the midgut tissue of Dysdercus peruvianus

The surface of midgut cells in Hemiptera is ensheathed by a lipoprotein membrane (the perimicrovillar membrane), which delimits a closed compartment with the microvillar membrane, the so-called perimicrovillar space. In Dysdercus peruvianus midgut perimicrovillar space a soluble aminopeptidase maybe involved in the digestion of oligopeptides and proteins ingested in the diet. This D. peruvianus aminopeptidase was purified to homogeneity by ion-exchange chromatography on an Econo-Q column, hydrophobic interaction chromatography on phenyl-agarose column and preparative polyacrylamide gel electrophoresis. The results suggested that there is a single molecular species of aminopeptidase in D. peruvianus midgut. Molecular mass values for the aminopeptidase were estimated to be 106 kDa (gel filtration) and 55 kDa (SDS-PAGE), suggesting that the enzyme occurs as a dimer under native conditions. Kinetic data showed that D. peruvianus aminopeptidase hydrolyzes the synthetic substrates LpNA, RpNA, A beta NA and AsnMCA (K(m)s 0.65, 0.14, 0.68 and 0.74 mM, respectively). The aminopeptidase activity upon LpNA was inhibited by EDTA and 1,10-phenanthroline, indicating the importance of metal ions in enzyme catalysis. One partial sequence of BLAST-identified aminopeptidase was found by random sequencing of the D. peruvianus midgut cDNA library. Semi-quantitative RT-PCR analysis showed that the aminopeptidase genes were expressed throughout the midgut epithelium, in the epithelia of V1, V2 and V3. Malphigian tubules and fat body, but it was not expressed in the salivary glands. These results are important in furthering our understanding of the digestive process in this pest species. (c) 2010 Elsevier Inc. All rights reserved.

Characterization and selection of Bacillus thuringiensis isolates effective against Sitophilus oryzae

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Proteinogramas séricos de ratos Wistar experimentalmente infectados com Trypanosoma evansi

Estabeleceu-se o perfil eletroforético de proteínas séricas de ratos Wistar experimentalmente infectados com Tripanosoma evansi, utilizando-se 40 ratos, distribuídos em oito grupos de cinco animais cada. Um grupo foi mantido como testemunho (G1), e os demais (G2 a G8) foram inoculados, via intraperitoneal, com cerca de 10³tripomastigota de T. evansi. Amostras de sangue para obtenção de soro foram coletadas no quinto (G2), 10º (G3), 15º (G4), 30º (G5), 45º (G6), 60º (G7) e 75º (G1 e G8) dia após as inoculações. O fracionamento das proteínas foi realizado pela técnica SDS-PAGE. Foram identificadas 31 proteínas, sendo sete de fase aguda: ceruloplasmina (101KD), hemopexina (83KD), transferrina (75KD), albumina (66KD), antitripsina (60KD), haptoglobina (44KD) e glicoproteína ácida (38KD). As proteínas com pesos moleculares 12KD; 22KD; 25KD; 28KD; 32,5KD; 35KD; 53,5KD; 63KD e 72KD apareceram apenas nos ratos inoculados com T. evansi.

Proteinograma sérico de bovinos da raça Curraleir

Estudou-se o perfil eletroforético das proteínas séricas de bovinos sadios da raça Curraleiro por meio da técnica de eletroforese em gel de acrilamida contendo dodecil sulfato de sódio. Utilizaram-se amostras de soro sanguíneo de 228 bovinos da raça Curraleiro, 51 machos e 177 fêmeas, com idades entre sete meses e 12 anos, pertencentes a dois rebanhos localizados nos Estados de Goiás e Tocantins. Foram quantificadas proteína total e concentração plasmática de fibrinogênio. Verificaram-se variações nas concentrações das diferentes frações proteicas. Foram detectadas 26 proteínas e identificadas 10 delas. A ceruloplasmina esteve ausente em 78,1% dos indivíduos, e a α-antitripsina não foi detectada em nenhum animal. Proteína total, globulina, IgA, IgG e fibrinogênio aumentaram com a idade e houve correlação positiva entre os níveis séricos de haptoglobina e α1-glicoproteína ácida.

Proteinograma e teores de cobre, ferro e zinco no soro sanguíneo de ovelhas da raça Santa Inês com mastite experimental por Staphylococcus aureus

Costa N.A., Simao L.C.V., Santos R.A., Afonso J.A.B., Fagliari J.J., Cardoso E.C., Soares P.C. & Mendonca C.L. 2010. [Proteinogram and serum concentrations of copper, iron and zinc in Santa Ines ewes with Staphylococcus aureus experimentally induced mastitis.] Proteinograma e teores de cobre, ferro e zinco no soro sanguineo de ovelhas da raca Santa Ines com mastite experimental por Staphylococcus aureus. Pesquisa Veterinaria Brasileira 30(5):435-442. Clinica de Bovinos, Campus Garanhuns, Universidade Federal Rural de Pernambuco (UFRPE), Avenida Bom Pastor s/n, Boa Vista, Caixa Postal 152, Garanhuns, PE 55292-901, Brazil. E-mail: carlalopes.mendonca@gmail.comThe aim of the present study was to evaluate the effect of Staphylococcus aureus experimentally induced mastitis on proteinogram and serum concentrations of cupper, iron and zinc levels of Santa Ines primiparous ewes. The right mammary gland of ten healthy ewes was inoculated with 1,0x10(4) UFC/mL of S. aureus. Clinical examination and determination of serum concentrations of proteins by electrophoresis in polyacrylamide gel (SDS-PAGE), cupper, iron and zinc, as well plasma level of fibrinogen were measured before the inoculation (control) and 12h, 24h, 36h, 48h, 60h, 72h, 84h, 96h, 108h, 120h, 132h, 168h, 180h, 288h and 336h after bacteria inoculation. All animals experimentally infected presented clinical mastitis and subsequent loss of mammary gland function. The electrophoretogram allowed the identification of 23 proteins with molecular weights (MW) ranged from 26.000 to 185.000 daltons (Da) including acute-phase proteins, IgG and IgA. A significant increase (P<0,05) in haptoglobin, ceruloplasmin, IgG and IgA concentrations was observed. Antitrypsin and acid glicoprotein concentrations did not alter. The levels of iron and zinc decreased and the cupper concentration increased. A positive correlation between plasma fibrinogen and serum ceruloplasmin (r=0.74), haptoglobin (r=0.62) and IgA (r=0.62) was also identified. Results showed the importance of ceruloplasmin and haptoglobin as acute-phase proteins in ewes with intramammary infections and confirms fibrinogen as an inflammatory marker because its high correlation with specific proteins. The alterations in the serum levels of Cu, Fe and Zn suggest the action of inflammatory mediators triggered by S. aureus.

Serum protein concentrations, including acute phase proteins, in calves experimentally infected with Salmonella Dublin

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Protein Hydrolysis by Immobilized and Stabilized Trypsin

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Isolation, solubility and in vitro hydrolysis of chickpea vicilin-like protein

The chickpea vicilin-like globulin was isolated and chromatographed on Sepharose CL-6B and Sephacryl S-300. The native globulin with a molecular weight of 140 kDa was resolved in Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in seven polypeptide bands in the range of 12.4-67 kDa. The solubility profile of the protein in water and NaCl solutions was typical of a legume globulin. The purified vicilin-like globulin, native and heated, was hydrolyzed by pepsin, trypsin and chymotrypsin. The hydrolysis patterns indicated that the native vicilin-like protein was only partially degraded by the enzymes in comparison with casein. Heating increased its susceptibility to hydrolysis relative to the native form, for all the enzymes. However, the results obtained by the pH-drop method revealed that the in vitro digestibility of the vicilin-like protein was not altered by heating, while 11 S-like and total globulins suffered a small increase, indicating that the structural characteristics of storage globulins may be important factors limiting the protein digestion. (c) 2007 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.

Production, purification and characterization of an extracellular inulinase from Kluyveromyces marxianus var. bulgaricus

The yeast Kluyveromyces marxianus var. bulgaricus produced large amounts of extracellular inulinase activity when grown on inulin, sucrose, fructose and glucose as carbon source, This protein has been purified to homogeneity by using successive DEAE-Trisacryl Plus and Superose 6 HR 10/30 columns. The purified enzyme showed a relative molecular weight of 57 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and 77 kDa by gel filtration in Superose 6 HR 10/30, Analysis by SDS-PAGE showed a unique polypeptide band with Coomassie Blue stain and nondenaturing PAGE of the purified enzyme obtained from media with different carbon sources showed the band, too, when stained for glucose oxidase activity, the optimal hydrolysis temperature for sucrose, raffinose and inulin was 55 degrees C and the optimal pH for sucrose was 4.75, the apparent K-m values for sucrose, raffinose and inulin are 4.58, 7.41 and 86.9 mg/ml, respectively, Thin layer chromatography showed that inulinase from K. marxianus var. bulgaricus was capable of hydrolyzing different substrates (sucrose, raffinose and inulin), releasing monosaccharides and oligosaccharides, the results obtained suggest the hypothesis that enzyme production was constitutive.

Production of Trichophyton mentagrophytes antigens and their characterization in mice

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Viable human buccal mucosa cells do not yield typical nucleoids: Impacts on the single-cell gel electrophoresis/comet assay

Buccal mucosa (BM) cells have been used in human biomonitoring studies for detecting DNA adducts and chromosomal damage in an epithelial cell population. In the present study, we have investigated if human BM cells are suitable for use in the single-cell gel electrophoresis (SCGE)/Comet assay as an approach for estimating the exposure of epithelial cells to DNA-damaging agents. Our results indicate that only a few cells from BM cell samples yield comets that can be analyzed by current methods, and that the yield of cells with comets is independent of the percentage of viable BM cells in the sample. Data generated after enzymatic enrichment of viable cells and immunomagnetic separation of epithelial cells suggest that most of the BM cells that do form comets are probably leukocytes. Moreover, by reevaluating specific cells after running the Comet assay, we found that viable epithelial BM cells give rise to atypical comets that are not included in the analysis. Comparing DNA migration patterns between small groups of smokers and nonsmokers indicated that long-term smoking had no effect on the subpopulation of cells that yield typical comets. Our results indicate that the SCGE assay, as it is commonly performed, may not be useful for genotoxicity monitoring in human epithelial BM cells.

Proteínas de fase aguda em cadelas com neoplasia mamária

As proteínas de fase aguda (PFA) apresentam concentrações séricas alteradas mediante processos infecciosos, inflamatórios e neoplásicos. Objetivou-se com este trabalho avaliar as variações séricas das PFA em cadelas portadoras de neoplasia mamária, comparando com a avaliação histológica e leucograma. As PFA foram avaliadas em 45 cadelas com tumor de mama, distribuídas nos grupos neoplasia benigna (n=13), maligna não ulcerada (n=24) e maligna ulcerada (n=8). O grupo controle foi composto por 20 cadelas saudáveis. Foram realizados o teste de eletroforese em gel de poliacrilamida contendo dodecil sulfato de sódio (SDS-PAGE) para identificar as PFA (albumina, ceruloplasmina, transferrina, haptoglobina Hp, α-1 antitripsina e α-1 glicoproteina ácida) e o teste ultrassensível para proteína C reativa (PCR). As pacientes com neoplasia mamária maligna ulcerada apresentaram elevações sérica para PCR e Hp e redução da albumina (P<0,05, One-Way ANOVA e Teste de Dunn). Nessas pacientes, foi observada correlação positiva entre o leucograma inflamatório e o aumento das PFA (P=0,002, Teste de Fisher) e não foram observadas correlações entre as PFA e os subtipos histológicos. Conclui-se que avaliações conjuntas da PCR, Hp e albumina podem ser utilizadas como ferramenta de auxílio diagnóstico e prognóstico em cadelas com neoplasia mamária.

Heparin-binding proteins of canine seminal plasma

Heparin-binding proteins (HBP) from seminal plasma have been expected to participate in modulation of the acrosomal reaction, and have been correlated with fertility in some species. However, they have not been described in the dog. The aim of this study was to document the HBPs of canine seminal plasma. Six pooled samples of seminal plasma from three crossbred dogs were used. The HBPs were isolated by heparin affinity chromatography and the fractions recovered were pooled. One-dimensional sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) was carried out on 12 and 18% vertical minigels. The stained gels were scanned and the molecular weight (kDa) values for each band within a lane were calculated by image analysis software. The electrophoresis analysis of the pooled eluded fractions identified 19 bands, with molecular weights varying from 61.5 to 5.2 kDa. Previous studies, using one-dimensional SDS-PAGE, identified two bands (67 and 58.6 kDa), which were positively correlated with some semen parameters (sperm motility, sperm vigor, percentage of morphologically normal sperm and plasma membrane integrity). The 61.5 kDa band detected in the present study apparently corresponded to the 58.6 kDa band identified previously. Canine seminal plasma contained HBP; since HBP modulate the acrosome reaction in other species, they may have the same function in the dog. Further studies are necessary to better characterize this protein and determine if it is associated with fertility in the dog. (c) 2006 Elsevier B.V. All rights reserved.