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J. A. Downie - One of the best experts on this subject based on the ideXlab platform.
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entry of rhizobium leguminosarum bv viciae into root hairs requires minimal nod factor specificity but subsequent infection thread growth requires nodo or node
Molecular Plant-microbe Interactions, 2000Co-Authors: Simon Walker, J. A. DownieAbstract:Using various mutant strains of Rhizobium leguminosarum bv. viciae, we have investigated the role of nodO in stimulating infection thread development in vetch and pea. Analysis of R. leguminosarum bv. viciae nodE and nodO mutants revealed no significant difference from the wild-type infection phenotype. Conversely, an R. leguminosarum bv. viciae nodE nodO double mutant was severely impaired in its ability to form normal infection threads. This strain displayed a number of novel infection-related events, including intracellular accumulations of bacteria at the base of root hairs, distended and enlarged infection threads, and reversed threads growing up root hairs. Since normal infection was seen in a nodE mutant, nodO must suppress these abnormal infection phenomena. A deletion mutant, retaining only the nodD and nodABCIJ genes, also formed intracellular accumulations at the base of root hairs. Addition of R. leguminosarum bv. viciae nodO could alleviate this phenotype and restore some infection thread for...
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entry of rhizobium leguminosarum bv viciae into root hairs requires minimal nod factor specificity but subsequent infection thread growth requires nodo or node
Molecular Plant-microbe Interactions, 2000Co-Authors: Simon Walker, J. A. DownieAbstract:Using various mutant strains of Rhizobium leguminosarum bv. viciae, we have investigated the role of nodO in stimulating infection thread development in vetch and pea. Analysis of R. leguminosarum bv. viciae nodE and nodO mutants revealed no significant difference from the wild-type infection phenotype. Conversely, an R. leguminosarum bv. viciae nodE nodO double mutant was severely impaired in its ability to form normal infection threads. This strain displayed a number of novel infection-related events, including intracellular accumulations of bacteria at the base of root hairs, distended and enlarged infection threads, and reversed threads growing up root hairs. Since normal infection was seen in a nodE mutant, nodO must suppress these abnormal infection phenomena. A deletion mutant, retaining only the nodD and nodABCIJ genes, also formed intracellular accumulations at the base of root hairs. Addition of R. leguminosarum bv. viciae nodO could alleviate this phenotype and restore some infection thread for...
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resistance to nodulation of cv afghanistan peas is overcome by nodx which mediates an o acetylation of the rhizobium leguminosarum lipo oligosaccharide nodulation factor
Molecular Microbiology, 1993Co-Authors: J. L. Firmin, Karen E Wilson, Russell W Carlson, Andrea E Davies, J. A. DownieAbstract:Only some strains of Rhizobium leguminosarum biovar viciae can efficiently nodulate varieties of peas such as cv. Afghanistan, which carry a recessive allele that blocks efficient nodulation by most western isolates of R.I. viciae. One strain (TOM) which can nodulate cv. Afghanistan peas has a gene (nodX) that is required to overcome the nodulation resistance. Strain TOM makes significantly lower amounts of lipo-oligosaccharide nodulation factors than other strains of R.I. viciae and this effect appears to be due to lower levels of nod gene induction. These nodulation factors are similar to those from other R.I. viciae strains in that they consist of an oligomer of four or five beta 1-4-linked N-acetylglucosamine residues in which the terminal non-reducing glucosamine carries an O-acetyl group and a C18:4 or C18:1 N-acyl group. However, one of the nodulation factors made by strain TOM differs from the factors made by other strains of R.I. viciae in that it carries an O-acetyl group on the C-6 of the reducing N-acetylglucosamine residue. This acetylation is NodX-dependent and the pentameric nodulation factor is acetylated on the reducing N-acetylglucosamine residue whereas the tetrameric nodulation factor is not. Although the nodL gene product is also an O-acetyl transferase (it O-acetylates the C-6 of the terminal non-reducing glucosamine), there is very little similarity between the amino acid sequences of these two acetyl transferases.
... ,kom Sukontason - One of the best experts on this subject based on the ideXlab platform.
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a molecular morphological and physiological comparison of english and german populations of calliphora vicina diptera calliphoridae
PLOS ONE, 2018Co-Authors: ... ,kwankamol Limsopatham, Richard Zehner, M J R Hall, Marcel A. Verhoff, ... ,narin Sontigun, ... ,kom Sukontason, Barbara Karolina ZajacAbstract:The bluebottle blow fly Calliphora vicina is a common species distributed throughout Europe that can play an important role as forensic evidence in crime investigations. Developmental rates of C. vicina from distinct populations from Germany and England were compared under different temperature regimes to explore the use of growth data from different geographical regions for local case work. Wing morphometrics and molecular analysis between these populations were also studied as indicators for biological differences. One colony each of German and English C. vicina were cultured at the Institute of Legal Medicine in Frankfurt, Germany. Three different temperature regimes were applied, two constant (16°C & 25°C) and one variable (17-26°C, room temperature = RT). At seven time points (600, 850, 1200, 1450, 1800, 2050, and 2400 accumulated degree hours), larval lengths were measured; additionally, the durations of the post feeding stage and intrapuparial metamorphosis were recorded. For the morphometric and molecular study, 184 females and 133 males from each C. vicina population (Germany n = 3, England n = 4) were sampled. Right wings were measured based on 19 landmarks and analyzed using canonical variates analysis and discriminant function analysis. DNA was isolated from three legs per specimen (n = 61) using 5% chelex. A 784 bp long fragment of the mitochondrial cytochrome b gene was sequenced; sequences were aligned and phylogenetically analyzed. Similar larval growth rates of C. vicina were found from different geographic populations at different temperatures during the major part of development. Nevertheless, because minor differences were found a wider range of temperatures and sampling more time points should be analyzed to obtain more information relevant for forensic case work. Wing shape variation showed a difference between the German and English populations (P<0.0001). However, separation between the seven German and English populations at the smaller geographic scale remained ambiguous. Molecular phylogenetic analysis by maximum likelihood method could not unambiguously separate the different geographic populations at a national (Germany vs England) or local level.
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A molecular, morphological, and physiological comparison of English and German populations of Calliphora vicina (Diptera: Calliphoridae)
2018Co-Authors: ... ,kwankamol Limsopatham, Hall, Martin J. R., Zehner Richard, Zajac, Barbara Karolina, Verhoff, Marcel A., ... ,narin Sontigun, ... ,kom Sukontason, Amendt JensAbstract:The bluebottle blow fly Calliphora vicina is a common species distributed throughout Europe that can play an important role as forensic evidence in crime investigations. Developmental rates of C. vicina from distinct populations from Germany and England were compared under different temperature regimes to explore the use of growth data from different geographical regions for local case work. Wing morphometrics and molecular analysis between these populations were also studied as indicators for biological differences. One colony each of German and English C. vicina were cultured at the Institute of Legal Medicine in Frankfurt, Germany. Three different temperature regimes were applied, two constant (16°C & 25°C) and one variable (17–26°C, room temperature = RT). At seven time points (600, 850, 1200, 1450, 1800, 2050, and 2400 accumulated degree hours), larval lengths were measured; additionally, the durations of the post feeding stage and intrapuparial metamorphosis were recorded. For the morphometric and molecular study, 184 females and 133 males from each C. vicina population (Germany n = 3, England n = 4) were sampled. Right wings were measured based on 19 landmarks and analyzed using canonical variates analysis and discriminant function analysis. DNA was isolated from three legs per specimen (n = 61) using 5% chelex. A 784 bp long fragment of the mitochondrial cytochrome b gene was sequenced; sequences were aligned and phylogenetically analyzed. Similar larval growth rates of C. vicina were found from different geographic populations at different temperatures during the major part of development. Nevertheless, because minor differences were found a wider range of temperatures and sampling more time points should be analyzed to obtain more information relevant for forensic case work. Wing shape variation showed a difference between the German and English populations (P
Simon Walker - One of the best experts on this subject based on the ideXlab platform.
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entry of rhizobium leguminosarum bv viciae into root hairs requires minimal nod factor specificity but subsequent infection thread growth requires nodo or node
Molecular Plant-microbe Interactions, 2000Co-Authors: Simon Walker, J. A. DownieAbstract:Using various mutant strains of Rhizobium leguminosarum bv. viciae, we have investigated the role of nodO in stimulating infection thread development in vetch and pea. Analysis of R. leguminosarum bv. viciae nodE and nodO mutants revealed no significant difference from the wild-type infection phenotype. Conversely, an R. leguminosarum bv. viciae nodE nodO double mutant was severely impaired in its ability to form normal infection threads. This strain displayed a number of novel infection-related events, including intracellular accumulations of bacteria at the base of root hairs, distended and enlarged infection threads, and reversed threads growing up root hairs. Since normal infection was seen in a nodE mutant, nodO must suppress these abnormal infection phenomena. A deletion mutant, retaining only the nodD and nodABCIJ genes, also formed intracellular accumulations at the base of root hairs. Addition of R. leguminosarum bv. viciae nodO could alleviate this phenotype and restore some infection thread for...
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entry of rhizobium leguminosarum bv viciae into root hairs requires minimal nod factor specificity but subsequent infection thread growth requires nodo or node
Molecular Plant-microbe Interactions, 2000Co-Authors: Simon Walker, J. A. DownieAbstract:Using various mutant strains of Rhizobium leguminosarum bv. viciae, we have investigated the role of nodO in stimulating infection thread development in vetch and pea. Analysis of R. leguminosarum bv. viciae nodE and nodO mutants revealed no significant difference from the wild-type infection phenotype. Conversely, an R. leguminosarum bv. viciae nodE nodO double mutant was severely impaired in its ability to form normal infection threads. This strain displayed a number of novel infection-related events, including intracellular accumulations of bacteria at the base of root hairs, distended and enlarged infection threads, and reversed threads growing up root hairs. Since normal infection was seen in a nodE mutant, nodO must suppress these abnormal infection phenomena. A deletion mutant, retaining only the nodD and nodABCIJ genes, also formed intracellular accumulations at the base of root hairs. Addition of R. leguminosarum bv. viciae nodO could alleviate this phenotype and restore some infection thread for...
F L Stoddard - One of the best experts on this subject based on the ideXlab platform.
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vc1 catalyzes a key step in the biosynthesis of Vicine from gtp in faba bean
bioRxiv, 2021Co-Authors: Emilie Bjornsdotter, Marcin Nadzieja, Wei Chang, Leandro Escobarherrera, Davide Mancinotti, Deepti Angra, Hamid Khazaei, Christoph Crocoll, Albert Vandenberg, F L StoddardAbstract:Abstract Faba bean is a widely adapted and high-yielding legume cultivated for its protein-rich seeds1. However, the seeds accumulate the anti-nutritional pyrimidine glucosides Vicine and conVicine, which can cause haemolytic anaemia—favism—in the 400 million individuals genetically predisposed by a deficiency in glucose-6-phosphate dehydrogenase2. Here, we identify the first enzyme associated with Vicine and conVicine biosynthesis, which we name VC1. We show that VC1 co-locates with the major QTL for Vicine and conVicine content and that the expression of VC1 correlates highly with Vicine content across tissues. We also show that low-Vicine varieties express a version of VC1 carrying a small, frame-shift insertion, and that overexpression of wild-type VC1 leads to an increase in Vicine levels. VC1 encodes a functional GTP cyclohydrolase II, an enzyme normally involved in riboflavin biosynthesis from the purine GTP. Through feeding studies, we demonstrate that GTP is a precursor of Vicine both in faba bean and in the distantly related plant bitter gourd. Our results reveal an unexpected biosynthetic origin for Vicine and conVicine and pave the way for the development of faba bean cultivars that are free from these anti-nutrients, providing a safe and sustainable source of dietary protein.
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determination of Vicine and conVicine from faba bean with an optimized high performance liquid chromatographic method
Food Research International, 2015Co-Authors: Marjo Pulkkinen, F L Stoddard, Annamaija Lampi, Maheswor Dev Gautam, Velimatti Ollilainen, Tuula Sontagstrohm, Hannu Salovaara, Vieno PiironenAbstract:Abstract A robust method was implemented to analyze Vicine and conVicine from faba bean and used to study variation among cultivars and growing years. Due to the different solubilities and stabilities of Vicine and conVicine, two extraction methods were compared, and conditions for high-performance liquid chromatography (HPLC) were optimized. The chosen method consisted of extraction with 7% perchloric acid with uridine as an internal standard, separation with a C18 column using 0.1% formic acid in water as the mobile phase, and UV detection at 273 nm. The response factors of Vicine and conVicine relative to uridine were determined using purchased Vicine and conVicine that was isolated from faba bean fractions by a preparative liquid chromatographic (LC) system coupled with mass spectrometry (MS). The established factors for Vicine and conVicine were 1.53 and 1.63, respectively. Their similarity makes it possible to use Vicine as a standard for quantification of conVicine in the absence of a conVicine standard and vice versa. Among 10 cultivars grown in the same year and location, Vicine and conVicine concentrations ranged from 5.2–7.6 mg/g dw and 2.1–3.6 mg/g dw, respectively. Variation among growing years was relatively small but statistically significant (P
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flanking snp markers for Vicine conVicine concentration in faba bean vicia faba l
Molecular Breeding, 2015Co-Authors: Hamid Khazaei, Donal M Osullivan, Huw Jones, Nicholas Pitts, Mikko J Sillanpaa, Pertti Parssinen, Outi Manninen, F L StoddardAbstract:The pyrimidine glycosides, Vicine and conVicine, limit the use of faba bean (Vicia faba L.) as food and feed. A single recessive gene, vc-, is responsible for a lowered Vicine–conVicine concentration. The biosynthetic pathway of these closely related compounds is not known, and the nearest available markers are several cM away from vc-. Improved markers would assist breeding and help to identify candidate genes. A segregating population of 210 F5 recombinant inbred lines was developed from the cross of Melodie/2 (low Vicine–conVicine) × ILB 938/2 (normal Vicine–conVicine), and Vicine–conVicine concentrations were determined twice on each line. The population was genotyped with a set of 188 SNPs. A strong, single QTL for Vicine–conVicine concentration was identified on chromosome I, flanked by markers 1.0 cM away on one side and 2.6 cM on the other. The interval defined by these markers in the model species Medicago truncatula includes about 340 genes, but no candidate genes were identified. Further fine mapping should lead to the identification of tightly linked markers as well as narrowing down the search for candidate regulatory or biosynthetic genes which could underlie the vc- locus.
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a baseline study of Vicine conVicine levels in faba bean vicia faba l germplasm
Plant Genetic Resources, 2013Co-Authors: Khalil Khamassi, F L Stoddard, Donal M Osullivan, Faycal Ben Jeddi, Doug Hobbs, Jose Irigoyen, Huw JonesAbstract:Vicine and conVicine are anti-nutritional compounds that accumulate in the cotyledons of faba beans. When humans consume beans with high levels of these compounds, it can cause a condition called favism in individuals harbouring a deficiency in the activity of their glucose-6-phosphate dehydrogenase. When faba beans are used in animal feeds, there can be effects on performance. These concerns have resulted in increasing interest within plant breeding in developing low Vicine and conVicine faba bean germplasm. In order to facilitate this objective, we developed a rapid and robust screening method for Vicine and conVicine, capable of distinguishing between faba beans that are either high (wild type) or low in Vicine and conVicine. In the absence of reliable commercial reference materials, we report an adaptation of a previously published method where a biochemical assay and spectral data were used to confirm the identity of our analytes, Vicine and conVicine. This method could be readily adopted in other facilities and open the way to the efficient exploitation of diverse germplasm in regions where faba beans play a significant role in human nutrition. We screened a collection of germplasm of interest to a collaborative plant breeding programme developing between the National Institute for Agricultural Botany in the UK and L'Institut Nationale d'Agronomie de Tunisie in Tunisia. We report the results obtained and discuss the prospects for developing molecular markers for the low Vicine and conVicine trait.
Carmen Burbano - One of the best experts on this subject based on the ideXlab platform.
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effect of roasting and boiling on the content of Vicine conVicine and l 3 4 dihydroxyphenylalanine in vicia faba l
Journal of Food Quality, 2012Co-Authors: Anaberta Cardadormartinez, Carmen Burbano, Mercedes Muzquiz, Karina Mayaocana, Alicia Ortizmoreno, Braulio E Herreracabrera, Gloria Davilaortiz, Mercedes Martinpedrosa, C Cuadrado, Cristian JimenezmartinezAbstract:The pyrimidine glycosides, Vicine and conVicine, are compounds of the genus Vicia, whereas their aglycone derivatives, diVicine and isouramil, are responsible for favism occurrence, and L-3,4-dihydroxyphenylalanine (L-DOPA) is a nonprotein amino acid precursor of dopamine in healthy neurons. The present work evaluated the effect of thermal treatment, which consisted of roasting and boiling, on the content of Vicine, conVicine and L-DOPA in mature cotyledons of 10 varieties of Mexican Vicia faba L. and determined the concentration of glycosides and L-DOPA by high-performance liquid chromatography. The raw cotyledons showed 2.88–6.10, 0.63–1.68 and 0.28–0.44 Vicine, conVicine and L-DOPA, respectively. The 12 and 40% and 30 and 61% decrease in Vicine and conVicine content, respectively, were observed to be the effect of roasting and boiling the samples. L-DOPA was totally removed by both thermal processes. In all analyzed samples, Vicine was the main compound; however, there were significant differences between varieties and thermal treatments. Practical Applications Vicine and conVicine glycosides are strongly implicated in favism, a hemolytic anemia in humans, and in poor performance of laying hens. There are reports of decreased egg weight, increase in the fragility of the yolk and a number of blood stains, and decreased fertility and hatchability of eggs. The characterization of new varieties of faba bean in their content of potentially toxic glycosides allows selection of those with the lowest possible content of such compounds. Also, the application of heat treatments that reduce glycosides will allow the use of seeds or flour to develop harmless food and feed ingredients.
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Content and distribution of Vicine, conVicine and l -DOPA during germination and seedling growth of two Vicia faba L. varieties
European Food Research and Technology, 2008Co-Authors: C. Goyoaga, Carmen Burbano, Mercedes M. Pedrosa, Eva Guillamón, A. Varela, Carmen Cuadrado, Mercedes MuzquizAbstract:This work examined the content and distribution of the pyrimidine glucosides Vicine and conVicine, and the nonproteic amino acid l-DOPA in cotyledons and embryo axes along the germination and seedling growth of Vicia faba L. vars. Alameda and Brocal. The behaviour of these compounds was similar in both varieties. Vicine and conVicine, implicated in favism disease, slowly declined in cotyledons. In embryo axis, Vicine levels were sharply reduced and conVicine amount was slightly increased as assay progressed. Total pyrimidine glucosides remained unchanged in the whole plant during the study. l-DOPA only appeared in the embryo axis of V. faba seeds and the highest content was observed in Brocal variety at 6 DAI (days after imbibition). The information provided in this study could be valuable for a possible role of embryo axis, rich in l-DOPA, for the treatment of Parkinson’s disease and also as a choice ingredient for functional foods or as nutraceutical.
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variation of favism inducing factors Vicine conVicine and l dopa during pod development in vicia faba l
Plant Foods for Human Nutrition, 1995Co-Authors: Carmen Burbano, Mercedes Muzquiz, C Cuadrado, Jose Ignacio CuberoAbstract:Changes in the concentrations of Vicine, conVicine and L-DOPA in two cultivars of Vicia faba L. seeds in different stages of pod development were determined by high performance liquid chromatography (HPLC). The Vicine and conVicine content was highest in fresh green cotyledons (moisture content about 80%) and gradually declined until a constant level was reached when seed dry matter percentage was around 40%. A similar pattern of variation in glucoside concentration was observed for the seed coat. The pods contained neither Vicine nor conVicine but they were particularly rich in L-DOPA. These compounds were not homogeneously distributed in the seeds.
