11 research outputs found
Development and validation of real-time PCR screening methods for detection of cry1A.105 and cry2Ab2 genes in genetically modified organisms
Primers and probes were developed for the element-specific detection of cry1A.105 and cry2Ab2 genes, based on their DNA sequence as present in GM maize MON89034. Cry genes are present in many genetically modified (GM) plants and they are important targets for developing GMO element-specific detection methods. Element-specific methods can be of use to screen for the presence of GMOs in food and feed supply chains. Moreover, a combination of GMO elements may indicate the potential presence of unapproved GMOs (UGMs). Primer-probe combinations were evaluated in terms of specificity, efficiency and limit of detection. Except for specificity, the complete experiment was performed in 9 PCR runs, on 9 different days and by testing 8 DNA concentrations. The results showed a high specificity and efficiency for cry1A.105 and cry2Ab2 detection. The limit of detection was between 0.05 and 0.01 ng DNA per PCR reaction for both assays. These data confirm the applicability of these new primer-probe combinations for element detection that can contribute to the screening for GM and UGM crops in food and feed samples
Genetic variability in four fish species (Pimelodus maculatus, Prochilodus lineatus, Salminus brasiliensis and Steindachneridion scripta) from Uruguay River basin
Phenotypic and molecular characterization of Staphylococcus xylosus: technological potential for use in fermented sausage
Comparative Proteomic Analysis of Two Varieties of Genetically Modified (GM) Embrapa 5.1 Common Bean (Phaseolus vulgaris L.) and Their Non-GM Counterparts
The genetically modified (GM) common
bean event Embrapa 5.1 was
commercially approved in Brazil in 2011; it is resistant to golden
mosaic virus infection. In the present work grain proteome profiles
of two Embrapa 5.1 common bean varieties, Pérola and Pontal,
and their non-GM counterparts were compared by two-dimensional gel
electrophoresis (2-DE) followed by mass spectrometry (MS). Analyses
detected 23 spots differentially accumulated between GM Pérola
and non-GM Pérola and 21 spots between GM Pontal and non-GM
Pontal, although they were not the same proteins in Pérola
and Pontal varieties, indicating that the variability observed may
not be due to the genetic transformation. Among them, eight proteins
were identified in Pérola varieties, and four proteins were
identified in Pontal. Moreover, we applied principal component analysis
(PCA) on 2-DE data, and variation between varieties was explained
in the first two principal components. This work provides a first
2-DE-MS/MS-based analysis of Embrapa 5.1 common bean grains
Development of Plasmid DNA Reference Material for the Quantification of Genetically Modified Common Bean Embrapa 5.1
The
genetically modified (GM) common bean Embrapa 5.1 was recently
approved for commercialization. The reliable detection and quantification
of GM organisms is strongly dependent on validated methods as well
as calibration systems. This work presents the development of a calibrant
plasmid for Embrapa 5.1 common bean detection. The reaction parameters
were determined and compared for both the plasmid DNA (pDNA) and the
genomic DNA (gDNA). PCR efficiencies for pDNA were 81% for the construction-specific
assays and 76% for the taxon-specific assay, whereas for gDNA efficiencies
were 94 and 93%, respectively. The limits of detection (LOD) in both
qPCR assays were 10<sup>2</sup> and 10<sup>3</sup> copies of gDNA
and pDNA per PCR reaction, respectively. This is sufficient to detect
0.067 and 0.67% of GM common bean in 100 ng of DNA, respectively,
which is in agreement with detecting the 1% GM content required by
the Brazilian legislation