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Summary: Vietnam is one of the countries with the highest diversity of golden camellias in the world, with more than forty endemic species. However, studies on Vietnamese golden camellias need to be expanded to fill a knowledge gap on these species' chemical profiles and pharmacological properties. This qualitative study focuses on six golden camellias: four endemic species from Tam Dao district, Vinh Phuc province, including Camellia hakodae, Camellia phanii, Camellia tamdaoensis, Camellia tienii and two species commonly cultivated in Quang Ninh province including Camellia petelotii and Camellia euphlebia. A mutual profile of 131 metabolites was obtained by using widely targeted metabolomics analysis using ultra‐performance liquid chromatography coupled with tandem mass spectrometry. Comparative metabolomics was performed among leaf extracts of six golden teas, between young and mature leaves and between freeze‐drying and oven‐drying leaves to discriminate these species, and determine the effect of developmental stage and post‐harvesting method on the plant metabolism. The PLS‐DA model successfully illustrated a clear separation of the six species and suggested apigenin C‐glycoside derivatives as chemical markers for the diversity. Young and mature leaves of all six species also produced distinguished metabolomes, differentiated by mostly amino acid derivatives. The multivariate analysis also indicated the conversion of some flavonoids and amino acids induced by heat in the drying process. These results offer metabolite markers for quality control of Vietnamese golden camellias and recommendations for their usage and preparation. [ABSTRACT FROM AUTHOR]

SUMMARY: Glutathione (GSH) is required for various physiological processes in plants, including redox regulation and detoxification of harmful compounds. GSH also functions as a repository for assimilated sulfur and is actively catabolized in plants. In Arabidopsis, GSH is mainly degraded initially by cytosolic enzymes, γ‐glutamyl cyclotransferase, and γ‐glutamyl peptidase, which release cysteinylglycine (Cys‐Gly). However, the subsequent enzyme responsible for catabolizing this dipeptide has not been identified to date. In the present study, we identified At4g17830 as a Cys‐Gly dipeptidase, namely cysteinylglycine peptidase 1 (CGP1). CGP1 complemented the phenotype of the yeast mutant that cannot degrade Cys‐Gly. The Arabidopsis cgp1 mutant had lower Cys‐Gly degradation activity than the wild type and showed perturbed concentrations of thiol compounds. Recombinant CGP1 showed reasonable Cys‐Gly degradation activity in vitro. Metabolomic analysis revealed that cgp1 exhibited signs of severe sulfur deficiency, such as elevated accumulation of O‐acetylserine (OAS) and the decrease in sulfur‐containing metabolites. Morphological changes observed in cgp1, including longer primary roots of germinating seeds, were also likely associated with sulfur starvation. Notably, At4g17830 has previously been reported to encode an N2‐acetylornithine deacetylase (NAOD) that functions in the ornithine biosynthesis. The cgp1 mutant did not show a decrease in ornithine content, whereas the analysis of CGP1 structure did not rule out the possibility that CGP1 has Cys‐Gly dipeptidase and NAOD activities. Therefore, we propose that CGP1 is a Cys‐Gly dipeptidase that functions in the cytosolic GSH degradation pathway and may play dual roles in GSH and ornithine metabolism. Significance Statement: In this study, we identified At4g17830 (CGP1) as a Cys‐Gly dipeptidase that functions in the glutathione (GSH) degradation pathway and revealed its importance in plant metabolism and growth, especially under sulfur starvation. Notably, CGP1 has been reported as an N2‐acetylornithine deacetylase (NAOD) that participates in the ornithine biosynthesis pathway; therefore, our findings imply that CGP1 is a bifunctional enzyme that plays vital roles in both sulfur and nitrogen metabolism. [ABSTRACT FROM AUTHOR]

Summary: Soybean (Glycine max L. Merr.) is a major crop worldwide, providing essential dietary proteins and edible oils for agriculture, food, animal feed and biofuel industries. However, its limited genetic variation makes it vulnerable to harsh environmental conditions, and its chemical diversity was strongly reduced after long domestication. Wild soybean (Glycine soja Sieb. et Zucc.), the ancestor of the G. max, possesses a high level of genetic diversity and thus present a precious reservoir for improving cultivated soybean. Characterising metabolomes of different G. soja accessions is crucial in exploring metabolite accumulation patterns for developing metabolic breeding strategies. This study successfully revealed the metabolomes of sixty‐four seed lines of G. soja collected throughout Japan by a widely targeted metabolomics approach, therefore, providing a good source of information for further studies to induce the production of bioactive compounds and the defence mechanism to stress. [ABSTRACT FROM AUTHOR]

Summary: In Catharanthus roseus, monoterpenoid indole alkaloids (MIAs) are produced through the cooperation of four cell types, with final products accumulating in specialized cells known as idioblasts and laticifers. To explore the relationship between cellular differentiation and cell type‐specific MIA metabolism, we analyzed the expression of MIA biosynthesis in germinating seeds.Embryos from immature and mature seeds were observed via stereomicroscopy, fluorescence microscopy, and electron microscopy. Time‐series MIA and iridoid quantification, along with transcriptome analysis, were conducted to determine the initiation of MIA biosynthesis. In addition, the localization of MIAs was examined using alkaloid staining and imaging mass spectrometry (IMS).Laticifers were present in embryos before seed maturation. MIA biosynthesis commenced 12 h after germination. MIAs accumulated in laticifers of embryos following seed germination, and MIA metabolism is induced after germination in a tissue‐specific manner.These findings suggest that cellular morphological differentiation precedes metabolic differentiation. Considering the well‐known toxicity and defense role of MIAs in matured plants, MIAs may be an important defense strategy already in the delicate developmental phase of seed germination, and biosynthesis and accumulation of MIAs may require the tissue and cellular differentiation. [ABSTRACT FROM AUTHOR]

Hepatocytes can switch their metabolic processes in response to nutrient availability. However, the dynamics of metabolites (such as lactate, pyruvate, and ATP) in hepatocytes during the metabolic switch remain unknown. In this study, we visualized metabolite dynamics in primary cultured hepatocytes during recovery from glucose‐deprivation. We observed a decrease in the mitochondrial ATP concentration when glucose was administered to hepatocytes under glucose‐deprivation conditions. In contrast, there was slight change in the cytoplasmic ATP concentration. A decrease in mitochondrial ATP concentration was associated with increased protein synthesis rather than glycogen synthesis, activation of urea cycle, and production of reactive oxygen species. These results suggest that mitochondrial ATP is important in switching metabolic processes in the hepatocytes. [ABSTRACT FROM AUTHOR]