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

Over-expression of the Hybrid Aspen Homeobox PttKN1 Gene in Red Leaf Beet Induced Altered Coloration of Leaves

PttKN1 (Populus tremula × tremuloides KNOTTED1) gene belongs to the KNOXI gene family. It plays an important role in plant development, typically in meristem initiation, maintenance and organogenesis, and potentially in plant coloration. To investigate the gene functions further, it was introduced into red leaf beet by the floral dip method mediated via Agrobacterium tumefaciens. The transformants demonstrated typical phenotypes as with other PttKN1 transformants. These alterations were very different from the morphology of the wild type. Among them, morphological modification of changed color throughout the entire plant from claret of wild type to yellowish green was the highlight in those transgenic PttKN1-beet plants. The result of spraying selection showed that the PttKN1-beet plants had kanamycin resistance. PCR assay of the 35S-Promoter, NPTII and PttKN1 gene, PCR-Southern analysis of the NPTII and PttKN1 gene showed that the foreign PttKN1 gene had successfully integrated into the genome of beet plant. Furthermore, the results of RT-PCR analysis showed that the gene was ectopic expressed in transgenic plants. These data suggested that there is a correlation between the ectopic expression of PttKN1 gene and morphological alterations of beet plants. Pigment content assay showed that betaxanthins concentrations shared little difference between wild type and transgenic lines, while betacyanins content in transgenic plants was sharply decreased, indicating that the altered plant coloration of the transgenic beet plants may be caused by the changed betacyanins content. The tyrosinase study suggested that the sharply decreased of betacyanins content in transgenic plants was caused via the decreased tyrosinase level. Therefore, the reason for the altered plant coloration may be due to partial inhibition of betacyanin biosynthesis that was induced via the pleiotropic roles of PttKN1 gene

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

Optimized fabrication of DLP-based 3D printing calcium phosphate ceramics with high-precision and low-defect to induce calvarial defect regeneration

Acquiring high-performance calcium phosphate (CaP) ceramics via 3D printing is critical for their applications in bone regenerative repair. In current study, a complete process study of 3D printed CaP ceramics based on digital light processing (DLP) technology was performed to get the ideal implant for the regenerative repair of calvarial defects. The smaller particle size of initial powder would be more favorable to getting slurry with high solid content and low viscosity. CaP green body with high precision and high curing rate could be fabricated at the exposure energy density and exposure time of 6.20 mJ cm−2 and 2 s, respectively. Moreover, the post-curing treatment could eliminate the interlayer cracks and increase the curing rate from 69.78% to 93.91% of green body. After that, the mechanical strength of CaP ceramics increased by 46.34%. In-vitro cellular experiments showed that 3D printed CaP ceramics had good biocompatibility, and could promote the osteoblastic differentiation of BMSCs. In-vivo rat cranial defect implantation revealed 3D printed CaP ceramics exhibited better osteogenic ability than the commercial ones (BAM®), reaching the close level with the autografts. Overall, this study could provide a closed-loop solution for 3D printed CaP ceramics with high-precision and low-defect to induce bone regeneration

Identification and Characterization of β‑Lathyrin, an Abundant Glycoprotein of Grass Pea (Lathyrus sativus L.), as a Potential Allergen

Grass pea, a protein-rich, high-yielding, and drought-tolerant legume, is used as food and livestock feed in several tropical and subtropical regions of the world. The abundant seed proteins of grass pea are salt-soluble globulins, which can be separated into vicilins and legumins. In many other legumes, the members of vicilin seed proteins have been identified as major allergens. However, very little information is available on the allergens of grass pea. In this study, we have identified an abundant 47 kDa protein from grass pea, which was recognized by immunoglobulin E (IgE) antibodies from sera drawn from several peanut-allergic patients. The IgE-binding 47 kDa protein was partially purified by affinity chromatography on a Con-A sepharose column. Matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry analysis of the 47 kDa grass pea protein revealed sequence homology to 47 kDa vicilin from pea and Len c 1 from lentil. Interestingly the grass pea vicilin was found to be susceptible to pepsin digestion <i>in vitro</i>. We have also isolated a cDNA encoding the grass pea 47 kDa vicilin (β-lathyrin), and the deduced amino acid sequence revealed extensive homology to several known allergens, including those from peanut and soybean. A homology model structure of the grass pea β-lathyrin, generated using the X-ray crystal structure of the soybean β-conglycinin β subunit as a template, revealed potential IgE-binding epitopes located on the surface of the molecule. The similarity in the three-dimensional structure and the conservation of the antigenic epitopes on the molecular surface of vicilin allergens explains the IgE-binding cross-reactivity

Identification and Characterization of β‑Lathyrin, an Abundant Glycoprotein of Grass Pea (Lathyrus sativus L.), as a Potential Allergen

Grass pea, a protein-rich, high-yielding, and drought-tolerant legume, is used as food and livestock feed in several tropical and subtropical regions of the world. The abundant seed proteins of grass pea are salt-soluble globulins, which can be separated into vicilins and legumins. In many other legumes, the members of vicilin seed proteins have been identified as major allergens. However, very little information is available on the allergens of grass pea. In this study, we have identified an abundant 47 kDa protein from grass pea, which was recognized by immunoglobulin E (IgE) antibodies from sera drawn from several peanut-allergic patients. The IgE-binding 47 kDa protein was partially purified by affinity chromatography on a Con-A sepharose column. Matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry analysis of the 47 kDa grass pea protein revealed sequence homology to 47 kDa vicilin from pea and Len c 1 from lentil. Interestingly the grass pea vicilin was found to be susceptible to pepsin digestion <i>in vitro</i>. We have also isolated a cDNA encoding the grass pea 47 kDa vicilin (β-lathyrin), and the deduced amino acid sequence revealed extensive homology to several known allergens, including those from peanut and soybean. A homology model structure of the grass pea β-lathyrin, generated using the X-ray crystal structure of the soybean β-conglycinin β subunit as a template, revealed potential IgE-binding epitopes located on the surface of the molecule. The similarity in the three-dimensional structure and the conservation of the antigenic epitopes on the molecular surface of vicilin allergens explains the IgE-binding cross-reactivity

Metabolomics Approach To Understand Mechanisms of β‑<i>N</i>‑Oxalyl‑l‑α,β-diaminopropionic Acid (β-ODAP) Biosynthesis in Grass Pea (<i>Lathyrus sativus</i> L.)

A study was performed to identify metabolic processes associated with β-ODAP synthesis in grass pea using a metabolomics approach. GC–MS metabolomics was performed on seedlings at 2, 6, and 25 days after sowing. A total of 141 metabolites were detected among the three time points representing much of grass pea primary metabolism, including amino acids, carbohydrates, purines, and others. Principal component analysis revealed unique metabolite profiles of grass pea tissues among the three time points. Fold change, hierarchical clustering, and orthogonal projections to latent structures-discriminant analyses, and biochemical pathway ontologies were used to characterize covariance of metabolites with β-ODAP content. The data indicates that alanine and nitrogen metabolism, cysteine and sulfur metabolism, and purine, pyrimidine, and pyridine metabolism were associated with β-ODAP metabolism. Our results reveal the metabolite profiles in grass pea development and provide insights into mechanisms of β-ODAP accumulation and degradation