β-n-oxalyl-l-α, β -diaminopropionic acid (β -odap) content in lathyrus sativus: The integration of nitrogen and sulfur metabolism through β -cyanoalanine synthase

Grass pea (Lathyrus sativus L.) is an important legume crop grown mainly in South Asia and Sub-Saharan Africa. This underutilized legume can withstand harsh environmental conditions including drought and flooding. During drought-induced famines, this protein-rich legume serves as a food source for poor farmers when other crops fail under harsh environmental conditions; however, its use is limited because of the presence of an endogenous neurotoxic nonprotein amino acid β-N-oxalyl-l-α,β-diaminopropionic acid (β-ODAP). Long-term consumption of Lathyrus and β-ODAP is linked to lathyrism, which is a degenerative motor neuron syndrome. Pharmacological studies indicate that nutritional deficiencies in methionine and cysteine may aggravate the neurotoxicity of β-ODAP. The biosynthetic pathway leading to the production of β-ODAP is poorly understood, but is linked to sulfur metabolism. To date, only a limited number of studies have been conducted in grass pea on the sulfur assimilatory enzymes and how these enzymes regulate the biosynthesis of β-ODAP. Here, we review the current knowledge on the role of sulfur metabolism in grass pea and its contribution to β-ODAP biosynthesis. Unraveling the fundamental steps and regulation of β-ODAP biosynthesis in grass pea will be vital for the development of improved varieties of this underutilized legume

Grain legumes and human health

Since early civilisation in different continents, grain legumes have been a part of balanced diets together with cereals. In general the seeds from those two plant families give together a good source of essential amino acids and may have given an evolutionary advantage. A sustainable diet for vegetarians may not be possible without the protein-rich legumes. Consumed alone, legumes can be a mixed blessing because of their deficiency of some essential amino acids. This deficiency can be balanced in a varied diet containing components richer in tryptophan and the sulphur amino acid methionine and cysteine. Many legume species are exceptionally rich in secondary metabolites, some of which are beneficial to human health while without adequate processing through heating or leaching many can be detrimental to the health of the consumer. Soybean (Glycine max) is one of the most popular and also one of the more healthy species. The presence of genistein and other isoflavones makes it famous as an anti-cancer nutraceutical. Isoflavones and other phytoestrogens, occurring mainly in legumes, might be a factor promoting longevity. Other beneficial secondary metabolites are found among the non-protein amino acids. Legumes are very rich in an enormous variety of non-protein amino acids that can be beneficial or toxic. A beneficial non-protein amino acid occurs in high concentration in fenugreek seeds (Trigonella foenum-graecum), a component of curry, while a variety of toxic amino acids occurs in the genera Lathyrus and Vicia. Legume seeds also contain a variety of anti-nutritional factors that can be reduced by post-harvest processing such as fermentation or germination. Fermentation also improves the balance of essential amino acids. Numerous dietary products such as soy sauce or tempeh are traditional food ingredients derived from legumes

3-N-oxalyl-L-2,3-diaminopropanoic acid, a multifunctional plant metabolite of toxic reputation

3-N-oxalyl-L-2,3-diaminopropanoic acid (beta-ODAP) is a neuroexcitatory non- protein amino acid identified in grass pea (Lathyrus sativus L.) and in ginseng (Panax spp). Its presence in the drought tolerant grass pea is thought to be responsible for the crippling disease neurolathyrism, while in the longevity promoting ginseng it is named dencichine and praised for its haemostatic properties. Some properties of beta-ODAP are put in perspective

Synthesis and Conformational Studies of Peptidomimetics Containing a New Bifunctional Diketopiperazine Scaffold Acting as a \u3b2-Hairpin Inducer

A practical synthesis of a new bifunctional diketopiperazine (DKP) scaffold 1, formally derived from the cyclization of L-aspartic acid and (S)-2,3-diaminopropionic acid, is reported. DKP-1 bears a carboxylic acid and an amino functionalities in a cis relationship, which have been used to grow peptide sequences. Tetra-, penta-, and hexapeptidomimetic sequences were prepared by solution-phase peptide synthesis (Boc strategy). Conformational analysis of these derivatives was carried out by a combination of 1H NMR spectroscopy, IR spectroscopy, CD spectroscopy, and computer modeling, and reveals the formation of beta-hairpin mimics involving 10-membered and 18-membered H-bonded rings and a reverse turn of the growing peptide chain

Recently published Streptomyces genome sequences

This is the final version of the article. Available from Wiley via the DOI in this record.ntroductionMany readers of this journal will need no introduction tothe bacterial genusStreptomyces, which includes severalhundred species, many of which produce biotechnolo-gically useful secondary metabolites. The last 2 yearshave seen numerous publications describingStrepto-mycesgenome sequences (Table 1), mostly as shortgenome announcements restricted to just 500 wordsand therefore allowing little description and analysis. Ouraim in this current manuscript is to survey these recentpublications and to dig a little deeper where appro-priate. The genusStreptomyces is now one of the mosthighly sequenced, with 19 finished genomic sequences(Table 2) and a further 125 draft assemblies available inthe GenBank database as of 3rd of May 2014; by the timethis is published, no doubt there will be more. The reasonsgiven for sequencing this latest crop ofStreptomycesinclude production of industrially important enzymes, deg-radation of lignin, antibiotic production, rapidJames Harrison was supported by a PhD studentship from the Biotechnology and Biological Sciences Research Council

Expressed sequence tag analysis in Cycas, the most primitive living seed plant

BACKGROUND: Cycads are ancient seed plants (living fossils) with origins in the Paleozoic. Cycads are sometimes considered a 'missing link' as they exhibit characteristics intermediate between vascular non-seed plants and the more derived seed plants. Cycads have also been implicated as the source of 'Guam's dementia', possibly due to the production of S(+)-beta-methyl-alpha, beta-diaminopropionic acid (BMAA), which is an agonist of animal glutamate receptors. RESULTS: A total of 4,200 expressed sequence tags (ESTs) were created from Cycas rumphii and clustered into 2,458 contigs, of which 1,764 had low-stringency BLAST similarity to other plant genes. Among those cycad contigs with similarity to plant genes, 1,718 cycad 'hits' are to angiosperms, 1,310 match genes in gymnosperms and 734 match lower (non-seed) plants. Forty-six contigs were found that matched only genes in lower plants and gymnosperms. Upon obtaining the complete sequence from the clones of 37/46 contigs, 14 still matched only gymnosperms. Among those cycad contigs common to higher plants, ESTs were discovered that correspond to those involved in development and signaling in present-day flowering plants. We purified a cycad EST for a glutamate receptor (GLR)-like gene, as well as ESTs potentially involved in the synthesis of the GLR agonist BMAA. CONCLUSIONS: Analysis of cycad ESTs has uncovered conserved and potentially novel genes. Furthermore, the presence of a glutamate receptor agonist, as well as a glutamate receptor-like gene in cycads, supports the hypothesis that such neuroactive plant products are not merely herbivore deterrents but may also serve a role in plant signaling

El Niño-southern oscillations and lathyrism epidemics

Epidemics of lathyrism, a neurological syndrome of spastic paraparesis, have occurredduring severe droughts in Europe, Asia, and Africa for millenia. Causation is linked toexposure to β-N-oxalyl-L-α,β-diaminopropionic acid (β-L-ODAP), a neurotoxin in Lathyrussativus. Lathyrism shares neurological features with konzo, a syndrome of predominantlyspastic paraparesis which occurs during droughts in East and Central Africa and is linked to El Nino activity. This study was done to determine the relationship of lathyrism epidemics to phases of El Nino-southern oscillation (ENSO) and Pacific decadal oscillation (PDO), and to propose a model to explain why the geospatial distributions of lathyrism and konzo are non-overlapping. Contingency table of phases of ENSO and occurrence of lathyrism epidemics in Central Provinces, India from 1833–1902 was created and odds ratio was calculated. Wavelet spectra of time series of annual occurrence of lathyrism in Rewah district, India, and its coherence with ENSO and PDO from 1894–1920 were performed. Lathyrism epidemic was associated with El Nino phase of ENSO, odds ratio 378 (95 % 32–4475). Global spectra showed peaks at periodicity of 2.5 and 4.6 years for lathyrism; 2.7 and 5.0 years for PDO; and 2.5, 4.6, 7.0 years for ENSO. Spectrograms showed time-varying periodicities of 2.5–3.5 and 4.5–5.5 years for lathyrism; 2.0–3.0 and 6.5–9.0 years for ENSO; and 3.5 and 5.0 years for PDO, p < 0.0001. Spectral coherence were at 2.0–3.5 and 4.5–5.0 years for ENSO and lathyrism p < 0.0001, and 5.0 years for PDO and lathyrism p < 0.05. The droughts of El Ninos initiate dependence on Lathyrus sativus, which exposes the population to neurotoxic β-L-ODAP. Public health control of lathyrism epidemics should include development of models to forecast El Ninos and initiate food programmes in susceptible areas

KONZO : the IBRO Africa Regional Committee (ARC) organizes its first Global Advocacy Workshop for Neuroscience in Kinshasa

Neurological diseases such as epilepsy, konzo, or neurolathyrism are not well understood or even accepted as major causes of disability. It is important that the public – from parents and children to politicians and policymakers – be informed about the importance of brain research and how it can help understand the causes and develop cures or, at least, alleviate the symptoms of neurological diseases