Manuel Pineda

• Doctor
• Professor (Full) at University of Córdoba

Nucleoside hydrolases (NSH; nucleosidases) catalyze the cleavage of nucleosides into ribose and free nucleobases. These enzymes have been postulated as key elements controlling the ratio between nucleotide salvage and degradation. Moreover, they play a pivotal role in ureidic legumes by providing the substrate for the synthesis of ureides. Furtherm...

Germination and seedling development are crucial phases in a plant’s life cycle with economical and agronomical implications. The RNA quality in seeds is linked to seed viability, being an important agronomic trait since this leads to a loss in germination efficiency. In addition, RNA can be an important phosphorous reservoir in seeds, affecting th...

Nucleotides are the basic elements of the genetic material, participate in bio-energetic processes, are cofactors and components of secondary metabolites, etc. Nucleotide hydrolases (nucleotidases) are phosphatases that remove the 5’-phosphate group from the nucleotides and play a crucial role in nucleotide metabolism. In this study, genes encoding...

Drought is probably the most harmful stress affecting common bean crops. Domestication, worldwide spread and local farming practices has entailed the development of a wide variety of common bean genotypes with different degrees of resistance to water stress. In this work, physiological and molecular responses to water stress have been compared in t...

Drought is one of the most critical factors limiting legume crop productivity. Understanding the molecular mechanisms of drought tolerance in the common bean is required to improve the yields of this important crop under adverse conditions. In this work, RNA-seq analysis was performed to compare the transcriptome profiles of drought-stressed and we...

Nucleotides are molecules of great importance in plant physiology. In addition to being elementary units of the genetic material, nucleotides are involved in bio-energetic processes, play a role as cofactors, and are also components of secondary metabolites and the hormone cytokinin. The common bean (Phaseolus vulgaris) is a legume that transports...

The increase in soil salinization due to global climate change could cause large losses in crop productivity affecting, among other biological processes, to germination and seedling development. We have studied how salt stress affects nucleic acid degrading activities in radicles of common bean during seedling development. In radicles of common bea...

Xanthine dehydrogenase (XDH) is essential for the assimilation of symbiotically fixed nitrogen in ureidic le-gumes. Uric acid, produced in the reaction catalyzed by XDH, is the precursor of the ureides, allantoin and allantoate, which are the main N-transporting molecules in these plants. XDH and uric acid have been reported to be involved in the r...

Xanthine dehydrogenase (XDH) is essential for the assimilation of symbiotically fixed nitrogen in ureidic le-gumes. Uric acid, produced in the reaction catalyzed by XDH, is the precursor of the ureides, allantoin and allantoate, which are the main N-transporting molecules in these plants. XDH and uric acid have been reported to be involved in the r...

Horizontal gene transfer (HGT) is widespread among prokaryotes driving their evolution. In this paper, we review the potential impact in humans of the HGT between prokaryotes living in close association with humans in two scenarios: horizontal transfer in human microbiomes and transfer between microbes living in human managed environments. Although...

Ureides are nitrogenous compounds with a special function in some legume under nitrogen fixing conditions, the ureidic legumes. In this group, ureides are the predominant nitrogen transport molecule from nodules to the upper part, whereas amidic legumes use amides as nitrogen transport compounds. In this study, the ureide levels have been analysed...

BACKGROUND: There are many substances that can interfere with olive oil quality. Some of them are well characterized, but many others have an unknown origin. Saturated hydrocarbons make an extraordinary complex family of numerous molecules, some of them present naturally in vegetable oils. When major natural saturated hydrocarbons are analyzed by s...

Background: There are many substances that can interfere with olive oil quality. Some of them are well characterized, but many others have an unknown origin. Saturated hydrocarbons make an extraordinary complex family of numerous molecules, some of them present naturally in vegetable oils. When major natural saturated hydrocarbons are analyzed by...

This selection from the NCCN Guidelines for Ovarian Cancer focuses on the less common ovarian histopathologies (LCOHs), because new algorithms were added for LCOHs and current algorithms were revised for the 2016 update. The new LCOHs algorithms include clear cell carcinomas, mucinous carcinomas, and grade 1 (low-grade) serous carcinomas/endometrio...

Nucleotidases are phosphatases that catalyze the removal of phosphate from nucleotides, compounds with an important role in plant metabolism. A phosphatase enzyme, with high affinity for nucleotides monophosphate previously identified and purified in embryonic axes from French bean, has been analyzed by MALDI TOF/TOF and two internal peptides have...

Una exploración de los grupos de presión, formadores de opinión y tomadores de decisión. Este estudio se pregunta acerca de la posibilidad factible de un nuevo enfoque sobre la regulación del Cannabis en El Salvador. Se trata de una investigación exploratoria que sondeando grupos de presión, formadores de opinión y tomadores de decisión en sus po...

Background and AimsDrought is the principal constraint on world production of legume crops. There is considerable variability among genotypes in sensitivity of nitrogen fixation to drought, which has been related to accumulation of ureides in soybean. The aim of this study was to search for genotypic differences in drought sensitivity and ureide ac...

Allantoate degradation is an essential step for recycling purine-ring nitrogen in all plants, but especially in tropical legumes where the ureides allantoate and allantoin are the main compounds used to store and transport the nitrogen fixed in nodules. Two enzymes, allantoate amidohydrolase (AAH) and allantoate amidinohydrolase (allantoicase), cou...

In common bean, asparagine synthetase (AS; EC 6.3.5.4) is encoded by three members of a multigene family called PVAS1, PVAS2 and PVAS3. Two of these genes, PVAS1 and PVAS2, have been extensively studied, but little is known about PVAS3, remaining unclear whether PVAS3 function is redundant to the other AS or if it plays a specific role in Phaseolus...

Elevated CO2 concentrations were found to cause early senescence during leaf development in sunflower (Helianthus annuus L.) plants, probably by reducing nitrogen availability since key enzymes of nitrogen metabolism, including nitrate reductase (NR); glutamine synthetase (GS) and glutamate dehydrogenase (GDH), were affected. Elevated CO2 concentra...

Drought stress is a major factor limiting symbiotic nitrogen fixation (NF) in soybean crop production. However, the regulatory mechanisms involved in this inhibition are still controversial. Soybean plants were symbiotically grown in a split-root system (SRS), which allowed for half of the root system to be irrigated at field capacity while the oth...

The ureides allantoin and allantoate are key molecules in the transport and storage of nitrogen in ureide legumes. In shoots and leaves from Phaseolus vulgaris plants using symbiotically fixed nitrogen as the sole nitrogen source, ureide levels were roughly equivalent to those of nitrate-supported plants during the whole vegetative stage, but they...

Common bean (Phaseolus vulgaris) seedlings accumulate ureides derived from purines after germination. The first step in the conversion of purines to ureides is the removal of the 5'-phosphate group by a phosphatase that has not been established yet. Two main phosphatase activities were detected in the embryonic axes of common bean using inosine mon...

The ureides allantoin and allantoate are key molecules in the transport and storage of nitrogen in ureide legumes. In shoots and leaves from Phaseolus vulgaris plants using symbiotically fixed nitrogen as the sole nitrogen source, ureide levels were roughly equivalent to those of nitrate-supported plants during the whole vegetative stage, but they...

Several physicochemical parameters were determined to study the behavior of three commercial oils with different chemical composition in deep fat frying at 160°C. Peroxide value seems not to be an accurate tool to control the quality of frying oils. On the contrary, iodine value, conjugated diene, and viscosity gave useful information about the oil...

γ-Tocopherol methyltransferase (γ-TMT) (EC 2.1.1.95) is a very important enzyme in tocopherol biosynthesis in all photosynthetic organisms. In this paper, we present the functional characterization and expression analysis of γ-TMT from the unicellular green alga Chlamydomonas reinhardtii. Recombinant TMT1 enzyme was purified and characterized. The...

Ureidoglycolate is an intermediate in the degradation of the ureides, allantoin and allantoate, found in many organisms. In some leguminous plant species these compounds are used to transport recently fixed nitrogen in the root nodules to the aerial parts of the plant. In the present study, it was demonstrated that purified ureidoglycolases from ch...

Under water deficit, ureidic legumes accumulate ureides in plant tissues, and this accumulation has been correlated with the inhibition of nitrogen fixation. In this work we used a molecular approach to characterize ureide accumulation under drought stress in Phaseolus vulgaris. Accumulation of ureides, mainly allantoate, was found in roots, shoots...

We study the effects of diffusing opinions on the Deffuant et al. model for continuous opinion dynamics. Individuals are given the opportunity to change their opinion, with a given probability, to a randomly selected opinion inside an interval centered around the present opinion. We show that diffusion induces an order-disorder transition. In the d...

This letter focus on the effect of repulsive interactions on the adoption of an external message in an opinion model. With a simple change in the rules, we modify the Deffuant \emph{et al.} model to incorporate the presence of repulsive interactions. We will show that information receptiveness is optimal for an intermediate fraction of repulsive li...

The enzyme p-hydroxyphenylpyruvate dioxygenase (HPPD) is very important in prenylquinone biosynthesis in all photosynthetic organisms. In this study, we present the functional characterization and expression analysis of HPPD from the unicellular green alga Chlamydomonas reinhardtii P. A. Dang. Recombinant HPPD1 enzyme was purified and characterized...

Olive oil (OO) is the most representative food of the traditional Mediterranean Diet (MedDiet). Increasing evidence suggests that monounsaturated fatty acids (MUFA) as a nutrient, OO as a food, and the MedDiet as a food pattern are associated with a decreased risk of cardiovascular disease, obesity, metabolic syndrome, type 2 diabetes and hypertens...

Under water deficit, ureidic legumes accumulate ureides in plant tissues, and this accumulation has been correlated with the inhibition of nitrogen fixation. In this work we used a molecular approach to characterize ureide accumulation under drought stress in Phaseolus vulgaris. Accumulation of ureides, mainly allantoate, was found in roots, shoots...

We study the Deffuant et al model for continuous-opinion dynamics under the influence of noise. In the original version of this model, individuals meet in random pairwise encounters after which they compromise or not depending on a confidence parameter. Free will is introduced in the form of noisy perturbations: individuals are given the opportunit...

French bean (Phaseolus vulgaris) is a legume that transports most of the atmospheric nitrogen fixed in its nodules to the aerial parts of the plant as ureides. Changes in ureide content and in enzymatic activities involved in their metabolism were identified in the cotyledons and embryonic axes during germination and early seedling development. Acc...

A gene encoding a putative asparagine synthetase (AS; EC 6.3.5.4) has been isolated from common bean (Phaseolus vulgaris). A 2.4 kb cDNA clone of this gene (PVAS3) encodes a protein of 570 amino acids with a predicted molecular mass of 64,678 Da, an isoelectric point of 6.45, and a net charge of -5.9 at pH 7.0. The PVAS3 protein sequence conserves...

The difficulty of assaying asparagine synthetase (AS) (EC 6.3.5.4) activity in roots of soybean has been circumvented by measuring expression of the AS genes. Expression of three soybean asparagine synthetase (SAS) genes (SAS1, SAS2 and SAS3) was observed in roots of non-nodulated soybean plants cultivated on nitrate. Expression of these genes was...

Allantoinase (allantoin amidohydrolase, EC 3.5.2.5) catalyses the hydrolysis of allantoin to allantoic acid, a key reaction in the biosynthesis and degradation of ureides. This activity was determined in different tissues of French bean plants (Phaseolus vulgaris L.) which were grown under nitrogen-fixing conditions. Allantoinase activity was detec...

In tropical legumes like French bean (Phaseolus vulgaris) or soybean (Glycine max), most of the atmospheric nitrogen fixed in nodules is used for synthesis of the ureides allantoin and allantoic acid, the major long distance transport forms of organic nitrogen in these species. The purpose of this investigation was to characterise the allantoate de...

The antioxidant potential of roselle (Hibiscus sabdariffa L.) extracts was studied. Different plant organs, including seeds, stems, leaves, and sepals, were analyzed with respect to their water-soluble antioxidant capacity, lipid-soluble antioxidant capacity, and tocopherol content, revealing that roselle seeds are a good source of lipid-soluble an...

There is an increasing demand for natural antioxidants to replace synthetic additives in the food industry. The present work examines the potential of some wild and cultivated plants from the Mediterranean region as sources of natural antioxidants. Samples of different organs and tissues from each of these species were extracted with aqueous and or...

A ureidoglycolate-degrading activity was analysed in different tissues of French bean (Phaseolus vulgaris L.) plants during development. Activity was detected in all the tissues analysed, although values were very low in seeds before germination and in cotyledons. After radicle emergence, the activity increased due to high activity present in the a...

Chlamydomonas reinhardtü Dangeard, adenine or guanine can be used as the sole nitrogen source for growth by means of an inducible system which is repressed by ammonia. Cells grown on either adenine or guanine were able to take up both purines, although the adenine uptake rate was always about 40% of the guanine uptake rate. Both adenine and guanine...

Warm season N2-fixing legumes move fixed N from the nodules to the aerial portions of the plant primarily in the form of ureides, allantoin and allantoate, oxidation products of purines synthesized de novo in the nodule. Ureides are also products of purine turnover in senescing tissues, such as seedling cotyledons. A combination of biochemical and...

Ageing represents a great concern in developed countries because the number of people involved and the pathologies related with it, like atherosclerosis, morbus Parkinson, Alzheime's disease, vascular dementia, cognitive decline, diabetes and cancer. Epidemiological studies suggest that a Mediterranean diet (which is rich in virgin olive oil) decre...

Aging represents a great concern in developed countries because the number of people involved and the pathologies related with it, like atherosclerosis, Parkinson, Alzheimer, vascular dementia, cognitive decline, diabetes and cancer. Epidemiological studies suggest that a Mediterranean diet (which is rich in virgin olive oil) decreases the risk of...

1 Ageing represents a great concern in developed countries because the number of people involved and the pathologies related with it, like atherosclerosis, morbus Parkinson, Alzheime's disease, vascular dementia, cognitive decline, diabetes and cancer. 2 Epidemiological studies suggest that a Mediterranean diet (which is rich in virgin olive oil) d...

Asparagine synthetase (AS; EC 6.3.5.4) is encoded by two genes in the common bean (Phaseolus vulgaris L.). PVAS2, a cDNA coding for a type-II asparagine synthetase from this legume, was cloned into pUC18 and its protein product, a functional asparagine synthetase, was able to complement the Escherichia coli asparagine-auxotroph ER#4813. PVAS2 was s...

A complete cDNA and a genomic DNA fragment coding for urate oxidase (urate: oxygen oxidoreductase, EC 1.7.3.3) from chickpea (Cicer arietinum L.) were isolated and characterized. The 1032 bp cDNA (CAUR1) contains a complete open reading frame that encodes a 308 amino acid protein with a predicted size of 34.06 kDa and a pI of 9.38. This protein sho...

Allantoicase (allantoate amidinohydrolase, EC 3.5.3.4) from Chlamydomonas reinhardtii catalyses the degradation of allantoate to (−)ureidoglycolate and of (+)ureidoglycolate to glyoxylate, in both cases with urea as the other product. Allantoicase activity purified in buffers without any cations increased after manganese addition to the assay mixtu...

Bean leaf urate oxidase (host enzyme) activity increases in both compatible and incompatible interactions once the first haustorium has differentiated (1 day post-inoculation) after Uromyces phaseoli infection. Progressive development of the parasite in susceptible leaves leads to further enhancement of urate oxidase activity and both host and fung...

An on-line method to detect and quantify antioxidant species in complex extracts has been developed as a combination of conventional HPLC separation and a postcolumn reaction with phosphomolybdenum reagent at acidic pH. Sample analytes were chromatographed by HPLC, and the postcolumn formation of a phosphate/Mo(V) complex was detected at 598 nm wit...

Summary • Asparagine metabolism in sunflower (Helianthus annuus) was investigated by cDNA cloning, sequence characterization and expression analysis of three genes encoding different isoforms of asparagine synthetase (AS, EC 6.3.5.4). • The AS-coding sequences were searched for in leaves, roots and cotyledons by using a methodology based on the sim...

Uricase (urate: oxygen oxidoreductase; EC 1.7.3.3) from the rust Puccinia recondita was purified to electrophoretic homogeneity. Preparations with a specific activity of 8.4 U/mg were used for characterization of the enzyme, which showed a strong similarity to other plant and fungal urate oxidases. The enzyme had a pH optimum of 9.0, a K m of 35 μM...

A gene encoding a putative asparagine synthetase (AS; EC 6.3.5.4) has been isolated from common bean (Phaseolus vulgaris L.). A 2-kb cDNA clone of this gene (PVAS1) encodes a protein of 579 amino acids with a predicted molecular mass of 65,265 Da, an isoelectric point of 6.3, and a net charge of -9.3 at pH 7.0. The PVAS1 protein sequence conserves...

ABSTRACT: A ureidoglycolate-degrading activity was analyzed in different organs of chickpea (Cicer arietinum). Activity was detected in all the tissues analyzed, but highest levels of specific activity were found in pods, from which it has been purified and characterized. This is the first ureidoglycolate-degrading activity that has been purified t...

ABSTRACT An allantoate-degrading enzyme has been purified to electrophoretic homogeneity for the first time from a photosynthetic organism, the unicellular green algae Chlamydomonas reinhardtii. The purification procedure included a differential protein extraction followed by conventional steps such as ammonium sulfate fractionation, gel filtration...

Uricase (urate: oxygen oxidoreductase; EC 1.7.3.3) from bean (Phaseolusvulgaris) leaves and uredospores of two different rust fungi (Uromyces phaseoli and Uromyces fabae) has been purified to electrophoretic homogeneity by a procedure which includes xanthine–agarose affinity chromatography as the main step. Pure preparations had similar specific ac...

We have identified a new human cDNA, L-amino acid transporter-2 (LAT-2), that induces a system L transport activity with 4F2hc (the heavy chain of the surface antigen 4F2, also named CD98) in oocytes. Human LAT-2 is the fourth member of the family of amino acid transporters that are subunits of 4F2hc. The amino acid transport activity induced by th...

A spectrophotometric method has been developed for the quantitative determination of antioxidant capacity. The assay is based on the reduction of Mo(VI) to Mo(V) by the sample analyte and the subsequent formation of a green phosphate/Mo(V) complex at acidic pH. The method has been optimized and characterized with respect to linearity interval, repe...

Following a RT-PCR strategy based on the design of degenerate oligonucleotides resembling conserved domains of asparagine synthetase (AS; EC 6.3.5.4), we isolated a 2 kb cDNA clone (PVAS2) from root tissue of the common bean (Phaseolus vulgaris). PVAS2 encodes a protein of 584 amino acids with a predicted relative molecular mass of 65 810 Da, an is...

Expression of uncase (urate oxidase) fromChlamydomonas reinhardtii has been investigated by using specific polyclonal antibodies. By Western blot analyses performed under nondenaturing conditions, a 124 kDa protein band corresponding to active uricase was detected in protein extracts from cells cultured with urate or nitrogen-starved cells. This pr...

The green alga Chlamydomonas reinhardtii can use the ureides allantoin and allantoate as sole nitrogen sources. Once the uptake systems for allantoin and allantoate were induced, the uptake and growth rates were identical for the two ureides. However, the enzymatic activities involved in the degradation of the two ureides (allantoinase and allantoi...

Uricase (urate: oxygen oxidoreductase, EC␣1.7.3.3) from leaves of chickpea (Cicer arietimum L.), broad bean (Vicia faba major L.), and wheat (Triticum aestivum L.) has been purified to electrophoretic homogeneity by a procedure which includes xanthine-agarose affinity chromatography as the main step. Purification factors of 74 000–83 000 and recove...

The antifungal compound alpha-tomatine, present in tomato plants, has been reported to provide a preformed chemical barrier against phytopathogenic fungi. Fusarium oxysporum f. sp. lycopersici, a tomato pathogen, produces an extracellular enzyme inducible by alpha-tomatine. This enzyme, known as tomatinase, catalyzes the hydrolysis of alpha-tomatin...

A strain of Chlamydomonas reinhardtii, named ARF-1, which grows with the glutamine synthetase (GS) inhibitor L-methionine-S-sulfoximine (MSX), has been isolated and characterized. Mutant ARF-1 is affected at a single and dominant gene, tentatively assigned to the allele msr-1-2. Neither the uptake of ammonia nor the two GS isoenzyme activities of t...

Transport and assimilation of purines in the unicellular green alga Chlamydomonas reinhardtii are reviewed. Adenine, guanine, hypoxanthine, xanthine and urate are good nitrogen sources for growth of Chlamydomonas. These purines are transported by means of systems exhibiting saturable, hyperbolic kinetics lacking diffusion component, with very low K...

The objective was to study the lipoprotein levels in primary hyperuricaemic patients and to analyse their renal management or urates in order to check for some potential influence of altered lipid levels on the renal excretion of urates by this type of patient. Overall 115 male individuals were studied in five groups, namely: 30 primary hyperuricae...

Several physical and chemical methods for the solubilization and extraction of allantoinase and allantoicase from the unicellular green alga Chlamydomonas reinhardtii have been tested and compared. Of all the methods employed (i.e. freezing-thawing, extraction at high ionic strength, disruption with the French press, sonication, and detergent solub...

The objective of this study has been to analyse the stability of α-tocopherol in virgin olive oil when heated in a microwave oven and a frying pan, as well as the variation of acid value and peroxide value. The samples used in the microwave heating showed a α-tocopherol retention of 51% while the frying-pan heated samples showed 38%.

Summary Utilization of xanthine as the sole nitrogen source for growth byChlamydomonas reinhardtii cells involved the formation of a transient, intracellular pool of xanthine. Up to 20% of the total xanthine supplied to the medium was not assimilated after uptake but stored in the cells at concentrations that exceeded xanthine solubility in water....

A spectrophotometric assay for ureidoglycolase activity (both ureidoglycolate lyase and hydrolase), based on the reduction of glyoxylate to glycolate catalyzed by glyoxylate reductase or lactate dehydrogenase with the stoichiometric and continuous NADH oxidation, is described. The assay has been optimized for the amount of coupling enzyme, reagent...

Rhodobacter capsulatus E1F1 showed high cytosolic urease activity when growing on urea, purines, and purine metabolites as nitrogen source. Molecular mass ofR. capsulatus enzyme is similar to that of other bacteria and greatly differs from that of jack bean. Kinetic parameters of partially purifiedR. capsulatus enzyme resemble those described in ot...

We studied the renal urate excretory function in two groups of hyperuricaemic male patients composed of individuals with associated hyperlipidemia and hyperuricaemic-normolipidemic individuals, respectively. Both the hyperlipidemia and the hyperuricaemia were primary inasmuch as none of the patients studied was obese or had an above-normal alcohol...

Urate oxidase (urate: oxygen oxidoreductase, EC 1.7.3.3) from Chlamydomonas reinhardtii is a tetramer of Mr=124 000, composed of similar-sized subunits and containing four atoms of copper per enzyme molecule (J. M. Alamillo, J. Cárdenas and M. Pineda, Biochim Biophys. Acta, 1076 (1991) 203-208). The enzyme exhibits a strict specificity toward its s...

Xanthine dehydrogenase (XDH) from the unicellular green alga Chlamydomonas reinhardtii has been purified to electrophoretic homogeneity by a procedure which includes several conventional steps (gel filtration, anion exchange chromatography and preparative gel electrophoresis). The purified protein exhibited a specific activity of 5.7 units/mg prote...

An l-amino-acid oxidase (EC 1.4.3.1) that catalyzes the oxidative deamination of twelve l-amino acids has been purified 21-fold and with 14% yield to electrophoretic homogeneity from Chlamydomonas reinhardtii cells by ammonium-sulfate fractionation, gel filtration through Sephacryl and Superose, anion-exchange chromatography and preparative electro...

Anl-amino-acid oxidase (EC 1.4.3.1) that catalyzes the oxidative deamination of twelvel-amino acids has been purified 21-fold and with 14% yield to electrophoretic homogeneity fromChlamydomonas reinhardtii cells by ammonium-sulfate fractionation, gel filtration through Sephacryl and Superose, anion-exchange chromatography and preparative electropho...

Urate oxidase (urate: oxygen oxidoreductase, EC 1.7.3.3) from the unicellular green alga Chlamydomonas reinhardtii has been purified to electrophoretic and immunological homogeneity by a procedure which includes as main steps ammonium sulfate fractionation, gel filtration, ion exchange and xanthine-agarose affinity chromatography. The native enzyme...

Chlamydomonas reinhardtii cells consumed hypoxanthine and xanthine by means of active systems which promoted purine intracellular accumulation against a high concentration gradient. Both uptake and accumulation were also observed in mutant strains lacking xanthine dehydrogenase activity. Xanthine and hypoxanthine uptake systems exhibited very simil...

The gln-gamma gene, encoding the gamma subunit of glutamine synthetase in French bean (Phaseolus vulgaris), is strongly induced during nodule development. We have determined the nucleotide sequence of a 1.3-kilobase region at its 5' end and have identified several sequences common to the promoter regions of late nodulin genes from other legume spec...

We carried out a study of 43 male asymptomatic subjects with high levels of uric acid but showing no signs of arterial hypertension, obesity or alcohol abuse. Initially, we investigated cholesterol levels, triglycerides in blood serum and the very low density lipoprotein fraction. The results showed asymptomatic hyperuricemia, frequently associated...

Xanthine dehydrogenase (XDH, EC 1.2.1.37) of Chlamydomonas reinhardtii (Sager) 6145c wild strain has been isolated and characterized for the first time in a unicellular green alga. The enzyme has an Mr of 330 kDa, and FAD, molybdenum and iron are cofactors required for its activity as deduced from results obtained using specific inhibitors, 59Fe-la...

Purines and purine derivatives are utilized by many organisms as sources of nitrogen and energy or as precursors in nucleic acids synthesis. Prior to their utilization these compounds must enter the cells through different transport systems depending on the type of cells. Up to now it has been very hard to distinguish between the transport process...

Wild-type Chlamydomonas reinhardtii cells exhibited a peculiar NADH-nitrobluetetrazolium reductase (NADH diaphorase) activity when grown under conditions in which xanthine dehydrogenase (XDH) is present. This XDH-coinduced diaphorase was electrophoretically distinguishable from constitutive diaphorases, showed the same mobility as XDH and could be...