Similaridade genética de variedades brasileiras de cevada nua e cevada cervejeira avaliada por marcadores RAPD

A cevada (Hordeum vulgare L.) é amplamente empregada na produção de cerveja e na ração animal. Recentemente, este cereal tornou-se desejável na alimentação humana devido ao seu alto valor nutricional, principalmente da cevada nua ou sem casca. Existem diferenças nas características nutricionais e para malteação entre as diversas variedades de cevada. O procedimento RAPD é capaz de separar as variedades de cevada em vários níveis de similaridade. O objetivo desse trabalho foi analisar por RAPD seis variedades brasileiras de cevada nua e sete variedades de cevada cervejeira. Reações de PCR foram realizadas com onze iniciadores aleatórios. Um total de 34 fragmentos de amplificação foi obtido com cinco destes iniciadores. Baseado no coeficiente de similaridade de Jaccard, um dendrograma foi construído. As variedades de cevada apresentaram índice médio de similaridade de 0,53. Fragmentos monomórficos intravariedades permitiram a diferenciação entre as variedades. Os coeficientes médios de similaridade intravariedades encontram-se entre 0,53 e 0,85. Os marcadores RAPD detectados neste trabalho foram adequados para a diferenciação entre as variedades brasileiras de cevada.Barley (Hordeum vulgare L.) is widely used for brewing and animal feed. Recently, it has become desirable for human consumption due to its high nutritional significance, specially hull-less or naked barley. There are differences in nutritional and malting characteristics among barley varieties. RAPD procedure is able to separate barley varieties at various similarity levels. The aim of this work was the RAPD analysis of six Brazilian hull-less varieties and seven malting varieties. PCR reactions were performed with eleven random primers. A total of 34 RAPD fragments was obtained with five primers. A dendrogram was constructed based on the Jaccard similarity coefficient. Barley varieties displayed an average similarity coefficient of 0.53. Intravarietal monomorphic fragments allowed differentiation among varieties. The averages of intravarietal similarity coefficients ranged from 0.53 to 0.85. RAPD markers, detected in this work, were suitable for differentiation among Brazilian barley varieties

Structural stability of Staphylococcus xylosus lipase is modulated by Zn2+ ions

AbstractLipases are well-known enzymes extensively used in industrial biotransformation processes. Besides, their structural and catalytic characteristics have attracted increasing attention of several industries in the last years. In this work, we used biophysical and molecular modeling tools to assess structural properties of Staphylococcus xylosus lipase (SXL). We studied the thermal unfolding of this protein and its zinc-dependent thermotolerance. We demonstrated that SXL is able to be active and stable at moderate temperatures, but this feature is only acquired in the presence of Zn2+. Such characteristic indicates SXL as a zinc-dependent metallolipase

Antifreeze proteins in naturally cold acclimated leaves of Drimys angustifolia, Senecio icoglossus, and Eucalyptus ssp.

Summary Antifreeze proteins (AFPs) present in plants may inhibit ice recrystallization even at low concentrations, and show potential application to many frozen foods. This study evaluated the presence of antifreeze proteins in naturally cold acclimated and non-acclimated leaves of Drimys angustifolia, Senecio icoglossus and Eucalyptus ssp. No proteins were detected in apoplastic extracts of Eucalyptus ssp. Extracts of cold acclimated and non-acclimated S. icoglossus showed protein concentrations of 42.89 and 17.76 µg mL-1, both with bands between 25 and 37 kDa in the SDS-PAGE. However, they did not inhibit recrystallization. The extract of cold acclimated D. angustifolia contained a protein concentration of 95.17 µg mL-1, almost five times higher than the extract of non-acclimated D. angustifolia. In the extract of cold acclimated D. angustifolia, there was presence of ice recrystallization inhibitors. This extract showed a protein band just below 37 kDa and another more intense band between 20 and 25 kDa. It is the first time that the presence of antifreeze proteins in this species is being described

Genetic similarity of Brazilian hull-less and malting barley varieties evaluated by RAPD markers

Barley (Hordeum vulgare L.) is widely used for brewing and animal feed. Recently, it has become desirable for human consumption due to its high nutritional significance, specially hull-less or naked barley. There are differences in nutritional and malting characteristics among barley varieties. RAPD procedure is able to separate barley varieties at various similarity levels. The aim of this work was the RAPD analysis of six Brazilian hull-less varieties and seven malting varieties. PCR reactions were performed with eleven random primers. A total of 34 RAPD fragments was obtained with five primers. A dendrogram was constructed based on the Jaccard similarity coefficient. Barley varieties displayed an average similarity coefficient of 0.53. Intravarietal monomorphic fragments allowed differentiation among varieties. The averages of intravarietal similarity coefficients ranged from 0.53 to 0.85. RAPD markers, detected in this work, were suitable for differentiation among Brazilian barley varieties

Tuber proteome comparison of five potato varieties by principal component analysis

BACKGROUND: Data analysis of omics data should be performed by multivariate analysis such as principal component analysis (PCA). The way data are clustered in PCA is of major importance to develop some classification systems based on multivariate analysis, such as soft independent modeling of class analogy (SIMCA). In a previous study a one-class classifier based on SIMCA was built using microarray data from a set of potatoes. The PCA grouped the transcriptomic data according to varieties. The present work aimed to use PCA to verify the clustering of the proteomic profiles for the same potato varieties. RESULTS: Proteomic profiles of five potato varieties (Biogold, Fontane, Innovator, Lady Rosetta and Maris Piper) were evaluated by two-dimensional gel electrophoresis (2-DE) performed on two immobilized pH gradient (IPG) strip lengths, 13 and 24cm, both under pH range 4-7. For each strip length, two gels were prepared from each variety; in total there were ten gels per analysis. For 13cm strips, 199-320 spots were detected per gel, and for 24cm strips, 365-684 spots. CONCLUSION: All four PCAs performed with these datasets presented clear grouping of samples according to the varieties. The data presented here showed that PCA was applicable for proteomic analysis of potato and was able to separate the samples by varieties.</p