Combined Metabolomic and Quantitative RT-PCR Analyses Revealed the Synthetic Differences of 2-Acetyl-1-pyrroline in Aromatic and Non-Aromatic Vegetable Soybeans

Aroma is an important economic trait of vegetable soybeans, which greatly influences their market value. The 2-acetyl-1-pyrroline (2AP) is considered as an important substance affecting the aroma of plants. Although the 2AP synthesis pathway has been resolved, the differences of the 2AP synthesis in the aromatic and non-aromatic vegetable soybeans are unknown. In this study, a broad targeted metabolome analysis including measurement of metabolites levels and gene expression levels was performed to reveal pathways of aroma formation in the two developmental stages of vegetable soybean grains [35 (S5) and 40 (S6) days after anthesis] of the ‘Zhexian No. 8’ (ZX8, non-aromatic) and ZK1754 (aromatic). The results showed that the differentially accumulated metabolites (DAMs) of the two varieties can be classified into nine main categories including flavonoids, lipids, amino acids and derivatives, saccharides and alcohols, organic acids, nucleotides and derivatives, phenolic acids, alkaloids and vitamin, which mainly contributed to their phenotypic differences. Furthermore, in combination with the 2AP synthesis pathway, the differences of amino acids and derivatives were mainly involved in the 2AP synthesis. Furthermore, 2AP precursors’ analysis revealed that the accumulation of 2AP mainly occurred from 1-pyrroline-5-carboxylate (P5C), not 4-aminobutyraldehyde (GABald). The quantitative RT-PCR showed that the associated synthetic genes were 1-pyrroline-5-carboxylate dehydrogenase (P5CDH), ∆¹-pyrroline-5-carboxylate synthetase (P5CS), proline dehydrogenase (PRODH) and pyrroline-5-carboxylate reductase (P5CR), which further verified the synthetic pathway of 2AP. Furthermore, the betaine aldehyde dehydrogenase 2 (GmBADH2) mutant was not only vital for the occurrence of 2AP, but also for the synthesis of 4-aminobutyric acid (GABA) in vegetable soybean. Therefore, the differences of 2AP accumulation in aromatic and non-aromatic vegetable soybeans have been revealed, and it also provides an important theoretical basis for aromatic vegetable soybean breeding.     

Seed Quantity or Quality?—Reproductive Responses of Females of Two Dioecious Woody Species to Long-Term Fertilisation

Although seed quality and quantity, as well as reproductive performance are important life history stages of plants, little is known about the reproductive responses of trees to environmental changes such as increased anthropogenic deposition of nitrogen (N) and phosphorus (P). Dioecious plants are good models with which to test the environmental impact on female or male reproductive responses individually. We analysed effects of different long-term nutritional availability on the reproductive performance of two dioecious species (Taxus baccata L. and Juniperus communis L.) characterised by different life histories. By using pot experiments with vegetatively propagated plants grown in different fertilisation conditions, we observed an increase in plant growth and strobili production but a decrease in seed efficiency. Seeds produced by fertilised plants had greater seed mass. Fertiliser addition did not change C or N content nor the C/N ratio of T. baccata seeds, but increased N content and the N/P ratio; however, it did lower the C/N ratio in J. communis. Fertilisation did not change the metabolite profile in T. baccata but 18 metabolites were changed in J. communis. The study revealed new links between species life history, environmental changes, and reproduction. The findings imply that future environmental conditions may alter both seed productivity, and quality, as well as plant reproductive behaviour.     

Gut Microbiota and Short Chain Fatty Acids: Implications in Glucose Homeostasis

Gut microbiota encompasses a wide variety of commensal microorganisms consisting of trillions of bacteria, fungi, and viruses. This microbial population coexists in symbiosis with the host, and related metabolites have profound effects on human health. In this respect, gut microbiota plays a pivotal role in the regulation of metabolic, endocrine, and immune functions. Bacterial metabolites include the short chain fatty acids (SCFAs) acetate (C2), propionate (C3), and butyrate (C4), which are the most abundant SCFAs in the human body and the most abundant anions in the colon. SCFAs are made from fermentation of dietary fiber and resistant starch in the gut. They modulate several metabolic pathways and are involved in obesity, insulin resistance, and type 2 diabetes. Thus, diet might influence gut microbiota composition and activity, SCFAs production, and metabolic effects. In this narrative review, we discuss the relevant research focusing on the relationship between gut microbiota, SCFAs, and glucose metabolism.     

The impact of genomics on crops for industry

The complete sequence of the genomes of two model plants is now available together with technology for the parallel analysis of thousands of genes, the proteins that they encode and the metabolites whose production they control. This review focuses on application of these technologies to engineer output characteristics of crops specifically relevant to non‐food use. Following a brief introduction to the resources available for genomic analysis, some examples are provided of how genomics is enabling both transgenic and non‐GM manipulation of agricultural materials such as carbohydrates, oils, fibres and speciality chemicals for use as industrial feedstocks. Copyright © 2006 Society of Chemical Industry     

Insights into Metabolite Diagnostic Biomarkers for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a persistent and unexplained pathological state characterized by exertional and severely debilitating fatigue, with/without infectious or neuropsychiatric symptoms, and with a minimum duration of 6 consecutive months. Its pathogenesis is not fully understood. There are no firmly established diagnostic biomarkers or treatment, due to incomplete understanding of the etiology of ME/CFS and diagnostic uncertainty. Establishing a biomarker for the objective diagnosis is urgently needed to treat a lot of patients. Recently, research on ME/CFS using metabolome analysis methods has been increasing. Here, we overview recent findings concerning the metabolic features in patients with ME/CFS and the animal models which contribute to the development of diagnostic biomarkers for ME/CFS and its treatment. In addition, we discuss future perspectives of studies on ME/CFS.