Maillard reaction products (MRPs) of xylose with phenylalanine and xylose with proline exhibit high antibacterial activity. However, the active antibacterial compounds in MRPs have not yet been identified or isolated. This study aimed to isolate the active compounds in the two antibacterial MRPs.
View Article and Find Full Text PDF-12-oxo-Phytodieneoic acid-α-monoglyceride () was isolated from . The chemical structure of was elucidated based on exhaustive 1D and 2D NMR spectroscopic measurements and supported by FDMS and HRFDMS data. The absolute configuration of the -OPDA moiety in was determined by comparison of H NMR spectra and ECD measurements.
View Article and Find Full Text PDFA novel isocoumarin was isolated from the mycelia of the dark septate endophytic fungus . The chemical structure was determined to be 8-hydroxy-6-methoxy-3,7-dimethyl-1-2-benzopyran-1-one based on mass spectrometry, H-nuclear magnetic resonance (NMR), and C-NMR spectroscopic analyses, including 2D-NMR experiments. The isolated compound inhibited root growth of , suggesting its potential as a plant growth regulator.
View Article and Find Full Text PDFResearchers have established that (+)-7-iso-jasmonic acid ((+)-7-iso-JA) is an intermediate in the production of cis-jasmone (CJ); however, the biosynthetic pathway of CJ has not been fully described. Previous reports stated that CJ, a substructure of pyrethrin II produced by pyrethrum (Tanacetum cinerariifolium), is not biosynthesized through this biosynthetic pathway. To clarify the ambiguity, stable isotope-labelled jasmonates were synthesized, and compounds were applied to apple mint (Mentha suaveolens) via air propagation.
View Article and Find Full Text PDFAcyl glucoses are a group of specialized metabolites produced by Solanaceae. , a wild-type tomato plant, produces acyl glucoses in its hair-like epidermal structures known as trichomes. These compounds have been found to be herbicides, microbial growth inhibitors, or allelopathic compounds.
View Article and Find Full Text PDFSignificanceStrigolactones (SLs) are a group of apocarotenoid hormones, which regulates shoot branching and other diverse developmental processes in plants. The major bioactive form(s) of SLs as endogenous hormones has not yet been clarified. Here, we identify an methyltransferase, CLAMT, responsible for the conversion of an inactive precursor to a biologically active SL that can interact with the SL receptor in vitro.
View Article and Find Full Text PDFJasmonoyl-isoleucine (JA-Ile) is a key signaling molecule that activates jasmonate-regulated flower development and the wound stress response. For years, JASMONATE RESISTANT1 (JAR1) has been the sole jasmonoyl-amino acid synthetase known to conjugate jasmonic acid (JA) to isoleucine, and the source of persisting JA-Ile in jar1 knockout mutants has remained elusive until now. Here we demonstrate through recombinant enzyme assays and loss-of-function mutant analyses that AtGH3.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
November 2021
New information is being accumulated for plant-derived oxylipins, such as jasmonic acid (JA) amino acid conjugates. However, these compounds have not being examined for their activity in promoting potato tuber formation. It was found that (-)-JA had the highest activity followed cis-(-)-OPDA, (+)-4, 5-didehydroJA, cis-(+)-OPDA-l-Ile, and (-)-JA-l-Ile, -Leu, -Phe, -Val, although iso-OPDA and 3,7-didehydroJA did not exhibit activity.
View Article and Find Full Text PDFJasmonic acid (JA) is a plant hormone involved in the defense response against insects and fungi. JA is synthesized from α-linolenic acid (LA) by the octadecanoid pathway in plants. 12-oxo-Phytodienoic acid (OPDA) is one of the biosynthetic intermediates in this pathway.
View Article and Find Full Text PDFNitro groups are often associated with synthetically manufactured compounds such as medicines and explosives, and rarely with natural products. Loquat emits a nitro compound, (2-nitroethyl)benzene, as a flower scent. The nitro compound exhibits fungistatic activity and is biosynthesised from l-phenylalanine via (E/Z)-phenylacetaldoxime.
View Article and Find Full Text PDFPlants can contain biosynthetic gene clusters (BGCs) that nominally resemble those found in microbes. However, while horizontal gene transmission is often observed in microbes, plants are limited to vertical gene transmission, implying that their BGCs may exhibit distinct inheritance patterns. Rice (Oryza sativa) contains two unlinked BGCs involved in diterpenoid phytoalexin metabolism, with one clearly required for momilactone biosynthesis, while the other is associated with production of phytocassanes.
View Article and Find Full Text PDFPhenolic acid decarboxylase (PAD) catalyzes the decarboxylation of hydroxycinnamic acids to produce hydroxystyrenes, which serve as starting materials for the production of polymers. Bamboo (Phyllostachys nigra; Pn) cells, a suitable host for producing phenylpropanoid-derived compounds, were transformed to express PAD of Bacillus amyloliquefaciens (BaPAD). BaPAD-transformed cells accumulated several metabolites that were not detected in wild-type Pn cells or BaPAD-negative transformant.
View Article and Find Full Text PDFRational metabolic-flow switching, which we proposed recently, is an effective strategy to produce an exogenous high-value natural product using transformed plant cells; the proof of this concept was demonstrated using bamboo (Phyllostachys nigra; Pn) cells as a model system. Pn cells were transformed to express 4-hydroxycinnamoyl-CoA hydratase/lyase of Pseudomonas putida KT2440 (PpHCHL), which catalyzes the formation of 4-hydroxybenzaldehyde and vanillin from p-coumaroyl-CoA and feruloyl-CoA, respectively. The PpHCHL-transformed cells accumulated glucose conjugates of 4-hydroxybenzoic acid and vanillic acid, indicating that the PpHCHL products (aldehydes) were further metabolized by inherent enzymes in the Pn cells.
View Article and Find Full Text PDFBackground & Aims: Levels of carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), and cancer antigen 125 (CA-125) in blood are used as markers to determine the response of patients with cancer to therapy, but are not used to identify patients with pancreatic cancer.
Methods: We obtained blood samples from 504 patients undergoing pancreatic surveillance from 2002 through 2018 who did not develop pancreatic cancer and measured levels of the tumor markers CA19-9, CEA, CA-125, and thrombospondin-2. Single-nucleotide polymorphisms (SNPs) in FUT3, FUT2, ABO, and GAL3ST2 that have been associated with levels of tumor markers were used to establish SNP-defined ranges for each tumor marker.
Nitrobacter winogradskyi is an abundant, intensively studied autotrophic nitrite-oxidizing bacterium, which is frequently used as a model strain in the two-step nitrification of ammonia (NH) to nitrate (NO) via nitrite (NO), either in activated sludge, agricultural field studies or more recently in artificial microbial consortia for organic hydroponics. We observed a hitherto unknown cobalt ion-dependent inhibition of cell growth and NO oxidation activity of N. winogradskyi in a mineral medium, which strongly depended on accompanying Ca and Mg concentrations.
View Article and Find Full Text PDF6-Tuliposide B (PosB), a major secondary metabolite that accumulates in tulip (), is converted to the antibacterial lactone, tulipalin B (PaB), by PosB-converting enzyme (TCEB). and , which encode TCEB, are specifically expressed in tulip pollen and roots, respectively, but are hardly expressed in other tissues (e.g.
View Article and Find Full Text PDFRice (Oryza sativa) produces a variety of labdane-related diterpenoids as phytoalexins and allelochemicals. The production of these important natural products has been partially elucidated. However, the oxidases responsible for production of the keto groups found in many of these diterpenoids have largely remained unknown.
View Article and Find Full Text PDFJasmonate (JA) and auxin are essential hormones in plant development and stress responses. While the two govern distinct physiological processes, their signaling pathways interact at various levels. Recently, members of the Arabidopsis indole-3-acetic acid (IAA) amidohydrolase (IAH) family were reported to metabolize jasmonoyl-isoleucine (JA-Ile), a bioactive form of JA.
View Article and Find Full Text PDFAppl Microbiol Biotechnol
September 2015
The oxygenation reactions catalyzed by cytochromes P450 (CYPs) play critical roles in plant natural products biosynthesis. At the same time, CYPs are one of most challenging enzymes to functionally characterize due to the difficulty of recombinantly expressing these membrane-associated monooxygenases. In the course of investigating rice diterpenoid biosynthesis, we have developed a synthetic biology approach for functional expression of relevant CYPs in Escherichia coli.
View Article and Find Full Text PDFPlants synthesize a huge variety of terpenoid natural products, including photosynthetic pigments, signaling molecules, and defensive substances. These are often produced as complex mixtures, presumably shaped by selective pressure over evolutionary timescales, some of which have been found to have pharmaceutical and other industrial uses. Elucidation of the relevant biosynthetic pathways can provide increased access (e.
View Article and Find Full Text PDFThe plant hormone jasmonate (JA) controls diverse aspects of plant immunity, growth, and development. The amplitude and duration of JA responses are controlled in large part by the intracellular level of jasmonoyl-L-isoleucine (JA-Ile). In contrast to detailed knowledge of the JA-Ile biosynthetic pathway, little is known about enzymes involved in JA-Ile metabolism and turnover.
View Article and Find Full Text PDFThe hormonal action of jasmonate in plants is controlled by the precise balance between its biosynthesis and catabolism. It has been shown that jasmonyl-L-isoleucine (JA-Ile) is the bioactive form involved in the jasmonate-mediated signaling pathway. However, the catabolism of JA-Ile is poorly understood.
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