36 research outputs found
Genetic relationship in Coffea species and parentage determination of interspecific hybrids using ISSR (Inter- Simple Sequence Repeat) markers
Development of microsatellite markers for identifying Brazilian Coffea arabica varieties
Microsatellite markers, also known as SSRs (Simple Sequence Repeats), have proved to be excellent tools for identifying variety and determining genetic relationships. A set of 127 SSR markers was used to analyze genetic similarity in twenty five Coffea arabica varieties. These were composed of nineteen commercially important Brazilians and six interspecific hybrids of Coffea arabica, Coffea canephora and Coffealiberica. The set used comprised 52 newly developed SSR markers derived from microsatellite enriched libraries, 56 designed on the basis of coffee SSR sequences available from public databases, 6 already published, and 13 universal chloroplast microsatellite markers. Only 22 were polymorphic, these detecting 2-7 alleles per marker, an average of 2.5. Based on the banding patterns generated by polymorphic SSR loci, the set of twenty-five coffee varieties were clustered into two main groups, one composed of only Brazilian varieties, and the other of interspecific hybrids, with a few Brazilians. Color mutants could not be separated. Clustering was in accordance with material genealogy thereby revealing high similarity
Accurate Inference of Subtle Population Structure (and Other Genetic Discontinuities) Using Principal Coordinates
Accurate inference of genetic discontinuities between populations is an essential component of intraspecific biodiversity and evolution studies, as well as associative genetics. The most widely-used methods to infer population structure are model-based, Bayesian MCMC procedures that minimize Hardy-Weinberg and linkage disequilibrium within subpopulations. These methods are useful, but suffer from large computational requirements and a dependence on modeling assumptions that may not be met in real data sets. Here we describe the development of a new approach, PCO-MC, which couples principal coordinate analysis to a clustering procedure for the inference of population structure from multilocus genotype data.PCO-MC uses data from all principal coordinate axes simultaneously to calculate a multidimensional "density landscape", from which the number of subpopulations, and the membership within subpopulations, is determined using a valley-seeking algorithm. Using extensive simulations, we show that this approach outperforms a Bayesian MCMC procedure when many loci (e.g. 100) are sampled, but that the Bayesian procedure is marginally superior with few loci (e.g. 10). When presented with sufficient data, PCO-MC accurately delineated subpopulations with population F(st) values as low as 0.03 (G'(st)>0.2), whereas the limit of resolution of the Bayesian approach was F(st) = 0.05 (G'(st)>0.35).We draw a distinction between population structure inference for describing biodiversity as opposed to Type I error control in associative genetics. We suggest that discrete assignments, like those produced by PCO-MC, are appropriate for circumscribing units of biodiversity whereas expression of population structure as a continuous variable is more useful for case-control correction in structured association studies
Genomic and Metabolomic Insights into the Natural Product Biosynthetic Diversity of a Feral-Hog-Associated Brevibacillus laterosporus Strain
The authors thank C. A. Mitchell for advice concerning the organization of the biosynthetic gene clusters in B. laterosporus PE36. We acknowledge J. Villemarete for providing access to the feral hog for sampling.
Author contributions
Conceived and designed the experiments: BSS RHC. Performed the experiments: CMT BWS JBK LSLP DRP. Analyzed the data: CMT BWS JBK LSLP DRP BSS RHC. Contributed reagents/materials/analysis tools: CMT BWS DRP. Wrote the paper: CMT BWS BSS RHC.Bacteria associated with mammals are a rich source of microbial biodiversity; however, little is known concerning the abilities of these microbes to generate secondary metabolites. This report focuses on a bacterium isolated from the ear of a feral hog from southwestern Oklahoma, USA. The bacterium was identified as a new strain (PE36) of Brevibacillus latersporus, which was shown via genomic analysis to contain a large number of gene clusters presumably involved in secondary metabolite biosynthesis. A scale-up culture of B. latersporus PE36 yielded three bioactive compounds that inhibited the growth of methicillin-resistant Staphylococcus aureus (basiliskamides A and B and 12-methyltetradecanoic acid). Further studies of the isolate's secondary metabolome provided both new (auripyrazine) and previously-described pyrazine-containing compounds. In addition, a new peptidic natural product (auriporcine) was purified that was determined to be composed of a polyketide unit, two L-proline residues, two D-leucine residues, one L-leucine residue, and a reduced L-phenylalanine (L-phenylalanol). An examination of the genome revealed two gene clusters that are likely responsible for generating the basiliskamides and auriporcine. These combined genomic and chemical studies confirm that new and unusual secondary metabolites can be obtained from the bacterial associates of wild mammals.Ye
Performance of wild-serbian ganoderma lucidum mycelium in treating synthetic sewage loading using batch bioreactor
The fluctuation of domestic wastewater characteristic inhibits the current conventional microbial-based treatment. The bioremediation fungi has received attention and reported to be an effective alternative to treat industrial wastewater. Similar efficient performance is envisaged for domestic wastewater whereby assessed performance of fungi for varying carbon-to-nitrogen ratios in domestic wastewater is crucial. Thus, the performance of pre-grown wild-Serbian Ganoderma lucidum mycelial pellets (GLMPs) was evaluated on four different synthetic domestic wastewaters under different conditions of initial pH (pH 4, 5, and 7) and chemical oxygen demand (COD) to nitrogen (COD/N) ratio of 3.6:1, 7.1:1, 14.2:1, and 17.8:1 (C3.6N1, C7.1N1, C14.2N1, and C17.8N1). The COD/N ratios with a constant concentration of ammonia–nitrogen (NH3–N) were chosen on the basis of the urban domestic wastewater characteristics sampled at the inlet basin of a sewage treatment plant (STP). The parameters of pH, COD, and NH3–N were measured periodically during the experiment. The wild-Serbian GLMPs efficiently removed the pollutants from the synthetic sewage. The COD/N ratio of C17.8N1 wastewater had the best COD and NH3–N removal, as compared to the lower COD/N ratio, and the shortest treatment time was obtained in an acidic environment at pH 4. The highest percentage for COD and NH3–N removal achieved was 96.0% and 93.2%, respectively. The results proved that the mycelium of GLMP has high potential in treating domestic wastewater, particularly at high organic content as a naturally sustainable bioremediation system
Cyclin-Dependent Kinase 6 Phosphorylates NF-kappa B P65 at Serine 536 and Contributes to the Regulation of Inflammatory Gene Expression
Peer reviewe
Isolation and characterization of eight microsatellite loci from the endangered plant species Hypochaeris salzmanniana (Asteraceae)
We report the isolation and characterization of eight microsatellite loci for Hypochaeris salzmanniana, an endangered species endemic to the southwestern coast of Spain and the Atlantic coast of Morocco. A total of 32 alleles were detected across a sample of 45 individuals, with an average number of 4.0 alleles per locus. The average polymorphic information content (PIC) was 0.533 and the observed (H O) and expected (H E) heterozygosity values varied from 0.022 to 0.978 and from 0.434 to 0.759, respectively. Five loci exhibited significant deviation from Hardy–Weinberg equilibrium (P ≤ 0.001) and three pairs of loci showed significant linkage disequilibrium (P ≤ 0.01). The eight loci were tested for transferability in three others species (H. arachnoidea, H. glabra, and H. radicata) belonging to the same section of H. salzmanniana. With the exception of locus Hsalz7, all loci successfully amplified in the three species. These preliminary data confirm the usefulness of microsatellite markers for assessing the ecology and genetic structure of H. salzmanniana and to understand the evolution of species within the section Hypochaeris.Claudete F. Ruas, Thiago J. Nakayama, M. A ´ . Ortiz, Mayra A. Kuroki, Tod F. Stuessy, Karin Tremetsberger, Eduardo A. Ruas, Melissa de Oliveira Santos, Salvador Talavera, Paulo M. Rua
Genetic Structure Of Quinoa (Chenopodium Quinoa Willd.) From The Bolivian Altiplano As Revealed By Rapd Markers
Quinoa (Chenopodium quinoa Willd.) is a pseudocereal originated from the Andes important for small farmers’ food security as well as for commercial production. Recently, it has been claimed that in Bolivia genetic erosion could result from the marginalization of the crop in the north and from its commercial standardization in the south. The aim of this study was to quantify the hierarchical structure of the genetic variation present in eight quinoa field populations, consisting
of cultivated and weedy individuals, representative of the altiplano and interandean valleys of Bolivia. Randomly amplified polymorphic DNA markers show that quinoa has a strong population structure and a high intra-population variation. An effect of geographical structure of
the populations was highlighted, due to population isolation, not simply linked to distance but more probably to climatic and orographic barriers present in the studied zone. The population structure is also reinforced by the limited seed exchanges among farmers as revealed by field interviews. This population structure appears related to three major biogeographic zones: the northern and central altiplano, the interandean valley, and the southern Salar. Intrapopulation genetic diversity was higher than that expected for a mainly autogamous species, and higher than
that reported in anterior studies based on germplasm collections. These results are commented in view of current knowledge on phylogeny and reproductive biology of the species, and their implications regarding genetic resources management are discussed
Development of Genic and Genomic SSR Markers of Robusta Coffee (Coffea canephora Pierre Ex A. Froehner)
Genetic similarity between coriander genotypes using ISSR markers Similaridade genética entre genótipos de coentro por marcadores ISSR
With the development of new cultivars, a precise genetic characterization is essential for improvement programs or for cultivar registration and protection. Molecular markers have been complementing the traditional morphological and agronomic characterization techniques because they are virtually unlimited, cover the whole genome and are not environmentally influenced. Genetic characterization constitutes the basis for studies involving estimates of genetic similarity. Therefore, the objective of the present study was to evaluate the genetic similarity between ten coriander genotypes (nine cultivars and one line) using ISSR markers. The cultivars used were: Americano, Asteca, Palmeira, Português, Santo, Supéria, Tabocas, Tapacurá, Verdão and the experimental line HTV-9299. The genetic similarity between the cultivars was estimated using 227 banded regions of ISSR molecular markers. The UBC 897 oligonucleotide generated the highest number of fragments (16), resulting in a higher polymorphism. The results indicate that the twenty-nine oligonucleotides chosen were satisfactory for detecting polymorphism. Based on the grouping analysis determined from the similarity data, there were two groups and two sub-groups. The calculated similarity for the genotypes varied from 52 to 75%. The lowest similarity was observed between Português and Verdão, at 52%. The highest similarity was found between Português and Palmeira, at 75%. The ISSR is efficient for identifying DNA polymorphism in coriander.<br>Com o surgimento de novas cultivares, uma caracterização genética precisa é essencial, visando à utilização em programas de melhoramento ou para fins de registros e ou proteção de cultivares. Marcadores moleculares vêm complementando a caracterização morfológica e agronômica tradicional, uma vez que são virtualmente ilimitados, cobrem todo o genoma e não são influenciados pelo ambiente. A caracterização genética constitui a base para trabalhos de estimativas de similaridade genética. Portanto, este trabalho teve como objetivo avaliar a similaridade genética entre dez genótipos de coentro (nove cultivares e uma linhagem) por meio de marcadores ISSR. As cultivares utilizadas foram Americano, Asteca, Palmeira, Português, Santo, Supéria, Tabocas, Tapacurá, Verdão e a linhagem experimental HTV-9299. A similaridade genética entre as cultivares foi estimada com base nos marcadores moleculares de ISSR, utilizando-se 227 regiões de bandas de ISSR. O oligonucleotídeo UBC 897 gerou o maior número de fragmentos (16), resultando em um maior polimorfismo. Os resultados indicam que os vinte e nove oligonucleotídeos escolhidos foram satisfatórios para detecção de polimorfismo. Como resultado da análise de agrupamento a partir dos dados de similaridade, verificou-se a presença de dois grupos e dois subgrupos. A similaridade calculada para os genótipos variou de 52 a 75%. A menor similaridade ficou entre Português e Verdão, com 52%. Já a maior similaridade foi obtida entre Português e Palmeira com 75%. O ISSR é eficiente na identificação de polimorfismo de DNA em coentro