A5063551924- Microbial Natural Products and Biosynthesis
- Fungal Biology and Applications
- Plant biochemistry and biosynthesis
- Synthetic Organic Chemistry Methods
- Carbohydrate Chemistry and Synthesis
- Natural product bioactivities and synthesis
- Bioactive Compounds and Antitumor Agents
- Phytochemical Studies and Bioactivities
- Marine Sponges and Natural Products
- Chemical Synthesis and Analysis
- Phytochemistry and Bioactive Compounds
- Plant-Microbe Interactions and Immunity
- Steroid Chemistry and Biochemistry
- Microbial Metabolic Engineering and Bioproduction
- Ubiquitin and proteasome pathways
- Microbial Metabolism and Applications
- Chemical synthesis and alkaloids
- Biochemical and Molecular Research
- Alkaloids: synthesis and pharmacology
- Cholinesterase and Neurodegenerative Diseases
- Synthesis and Biological Activity
- Plant Pathogens and Fungal Diseases
- Cancer, Hypoxia, and Metabolism
- Medicinal Plants and Neuroprotection
- Analytical Chemistry and Chromatography
RIKEN Center for Sustainable Resource Science
2015-2024
Universiti Sains Malaysia
2019-2023
RIKEN
2011-2023
RIKEN Advanced Science Institute
2009-2012
Arizona State University
2001-2011
Queensland Museum
2008
National Cancer Institute
2008
Kanagawa University
1998-2002
Cancer Research Institute
2001-2002
Asexual spores (conidia) are reproductive structures that play a crucial role in fungal distribution and survival. As conidia are, most cases, etiological agents of plant diseases lung disease, their stress resistance interaction with hosts have drawn increasing attention. In the present study, we investigated whether environmental temperature during conidiation affects tolerance human pathogenic fungus Aspergillus fumigatus. Conidia from 25°C culture showed lower to heat (60°C) oxidative...
Five new bufadienolides, 3β-formyloxyresibufogenin (1), 19-oxobufalin (2), 19-oxodesacetylcinobufagin (3), 6α-hydroxycinobufagin (4), and 1β-hydroxybufalin (5), have been isolated together with the previously known bufadienolides 6−20 from Chinese traditional drug "Ch'an Su". The structures were elucidated employing spectroscopic methods. Bufadienolides 1−5 provided significant inhibitory activity against KB HL-60 cancer cell lines. In addition, bufadienolide 1 was found active MH-60 line.
Autophagy is a bulk, nonspecific protein degradation pathway that involved in the pathogenesis of cancer and neurodegenerative disease. Here, we observed xanthohumol (XN), prenylated chalcone present hops (Humulus lupulus L.) beer, modulates autophagy. By using XN-immobilized beads, valosin-containing (VCP) was identified as XN-binding protein. VCP has been reported to be an essential for autophagosome maturation. Using vitro pull down assay, showed XN bound directly N domain, which known...
Genome sequencing of Streptomyces species has highlighted numerous potential genes secondary metabolite biosynthesis. The mining cryptic is important for exploring chemical diversity. Here we report the metabolite-guided genome and functional characterization a gene by biochemical studies. Based on systematic purification metabolites from sp. SN-593, isolated novel compound, 6-dimethylallylindole (DMAI)-3-carbaldehyde. Although many 6-DMAI compounds have been variety organisms, an enzyme...
Enzyme-catalyzed [4+2] cycloaddition has been proposed to be a key transformation process in various natural product biosynthetic pathways. Recently Fsa2 was found involved stereospecific trans-decalin formation during the biosynthesis of equisetin, potent HIV-1 integrase inhibitor. To understand mechanisms by which fsa2 determines stereochemistry reaction products, we sought an homologue that is pathway enantiomerically opposite analogue, and phm7, phomasetin. A decalin skeleton with...
Acetylcholinesterase (AChE) inhibitors remain the primary therapeutic drug that can alleviate Alzheimer's disease's (AD) symptoms. Several Cassia species have been shown to exert significant anti-AChE activity, which be an alternative remedy for AD. timoriensis and grandis are potential plants with but their phytochemical investigation is yet further conducted. The aims of this study were identify phytoconstituents C. evaluate inhibitory activity against AChE butyrylcholinesterase (BChE)....
QSAR analysis has been used to identify the essential structural requirements for increasing inhibitory activities of selected bufadienolides from Chinese drug Ch'an Su (and other sources) against primary liver carcinoma cell line PLC/PRF/5 (PLC) and derived colchicine-resistant (COL). The variable substituent domain proposed pharmacophore was investigated using a Comparative Molecular Field Analysis (CoMFA) approach. A model with considerable predictive ability obtained. In addition, CoMFA...
Bioassay-guided fractionation of extracts various plants, marine organisms, and microorganisms has led to the discovery new natural sources a number known compounds that have significant biological activity. The isolation interesting valuable cancer cell growth inhibitors including majusculamide C (1), axinastatin 5 (5), bengazoles A (6), B (7), E (8), manzamine (10), jaspamide (11), neoechinulin (19) been summarized.
Steroid bufenolides resulting from epoxidation of the 17β-2-pyrone ring bufadienolides are rare. Five 20,21-epoxybufenolides, namely, 20S,21-epoxyresibufogenin (1), 20R,21-epoxyresibufogenin (2), 3-O-formyl-20S,21-epoxyresibufogenin (3), 3-O-formyl-20R,21-epoxyresibufogenin (4), and 3-oxo-20S,21-epoxyresibufogenin (5), were isolated Chinese toad skin extract drug Ch'an Su. The structures elucidated by spectroscopic chemical methods. configuration at C-20 was assigned analysis difference NOE...
Systematic isolation of microbial metabolites has been performed to construct metabolite libraries or fraction libraries. A novel macrolactam, verticilactam (1), was isolated from a library Streptomyces spiroverticillatus JC-8444. The structure determined on the basis NMR and mass spectrometric measurements. 1 had unique 16-membered macrolactam skeleton including β-keto-amide moiety.
Two new phenylspirodrimane derivatives, stachybotrysin (1) and stachybotrylactone B (2), were isolated from the cultures of marine-derived fungus Stachybotrys sp. KCB13F013. The structures determined by analyzing spectroscopic data (1D 2D NMR MS) chemical transformation, including modified Mosher's method single-crystal X-ray structure analysis. Compound 1 exhibited an inhibitory effect on osteoclast differentiation in bone marrow macrophage cells via suppressing RANKL-induced activation...
Enzymes catalyzing [4+2] cycloaddition have attracted increasing attention because of their key roles in natural product biosynthesis. Here, we solved the X-ray crystal structures a pair decalin synthases, Fsa2 and Phm7, that catalyze intramolecular cycloadditions to form enantiomeric scaffolds during biosynthesis HIV-1 integrase inhibitor equisetin its stereochemical opposite, phomasetin. Computational modeling, using molecular dynamics simulations as well quantum chemical calculations,...
A microbial fraction library has been constructed as a part of RIKEN Natural Products Depository (NPDepo) to discover and isolate novel metabolites with unique biological activity from sources efficiently rapidly. The was made by systematic separation method based on basic chromatographic techniques. Each in the analyzed liquid chromatography/mass spectrometry (LC/MS) reveal physicochemical properties each metabolite within fraction, results were applied construct database for rapid...
Abstract In the course of screening our microbial metabolite fraction library, we identified a novel pyrrolizidinone compound, pyrrolizilactone. this study, report identification and characterization molecular target for pyrrolizilactone by using two phenotypic profiling systems. Cell morphology‐based analysis an imaging cytometer (MorphoBase) classified as proteasome inhibitor. Consistently, proteome‐based 2D difference gel electrophoresis (DIGE; ChemProteoBase) also demonstrated that is...
Despite much interest and studies toward the genus Podocarpus, anti-malarial evaluation of Podocarpus polystachyus's phytoconstituents remains lacking. Herein, P. polystachyus leaves their effect against Plasmodium falciparum were investigated for first time. One new natural product, 8ß,13ß-kaur-15-en-17-al (1), along with three known compounds, 8ß,13ß-kaur-15-en-17-ol (2) 13ß-kaur-16-ene (3), α-tocopherol hydroquinone (4) isolated via HR-ESI-MS NMR analyses. Compounds 1 2 inhibited growth...
The Sabatier principle states that catalytic activity can be maximized when the substrate binding affinity is neither too strong nor weak. Recent studies have shown of several hydrolases at intermediate values (Michaelis-Menten constant: K
Abstract To the best of our knowledge, enzymes that catalyse intramolecular Diels-Alder ([4+2] cycloaddition) reactions are frequently reported in natural product biosynthesis; however, no native utilising Lewis acid catalysis have been reported. Verticilactam is a representative member polycyclic macrolactams, presumably produced by spontaneous cycloaddition. We report [4+2] cycloadditions can be significantly accelerated ferredoxins (Fds), class small iron-sulphur (Fe-S) proteins. Through...