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Yi Guo, Na Zhang, Chunmei Chen, Jinfeng Huang, Xiao-Nian Li, Junjun Liu, Hucheng Zhu, Qingyi Tong, Jinwen Zhang, Zengwei Luo, Yongbo Xue, Yonghui Zhang
The new polyprenylated acylphloroglucinol derivatives 1-15 and the known furohyperforin (16) were isolated from the stems and leaves of Hypericum perforatum. Their structures were determined by analyses of NMR and HRESIMS data. Their absolute configurations were elucidated by a combination of electronic circular dichroism (ECD) and Rh2(OCOCF3)4-induced ECD, as well as X-ray diffraction crystallography. The new hyperforatin F (9) contains a unique acetyl functionality at C-1 of the bicyclo[3.3.1]nonane core...
April 26, 2017: Journal of Natural Products
Renyue Yang, Ping Li, Nana Li, Qian Zhang, Xue Bai, Lishuo Wang, Yiying Xiao, Lirong Sun, Quan Yang, Jian Yan
Mangosteen (Garcinia mangostana L.) is one of the most popular tropical fruits (called the "Queen of Fruits"), and is a rich source of oxygenated and prenylated xanthone derivatives. In the present work, phytochemical investigation has resulted in one new prenylated xanthone and 13 known xanthones isolated from the pericarp of G. mangostana. Their structures were established by spectroscopic data analysis, including X-ray diffraction. The new one was further tested for cytotoxic activity against seven cancer cell lines (CNE-1, CNE-2, A549, H490, PC-3, SGC-7901, U87), displaying the half maximal inhibitory concentration (IC₅0) values 3...
April 25, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Victor L Jensen, Michel R Leroux
Primary cilia are microtubule-based organelles found on most mammalian cell surfaces. They possess a soluble matrix and membrane contiguous with the cell body cytosol and plasma membrane, and yet, have distinct compositions that can be modulated to enable dynamic signal transduction. Here, we discuss how specialized ciliary compartments are established using a coordinated network of gating, trafficking and targeting activities. Cilium homeostasis is maintained by a size-selective molecular mesh that limits soluble protein entry, and by a membrane diffusion barrier localized at the transition zone...
April 19, 2017: Current Opinion in Cell Biology
Bing Lin, Jun-Fei Huang, Xiong-Wei Liu, Xi-Tao Ma, Xiong-Li Liu, Yi Lu, Ying Zhou, Feng-Min Guo, Ting-Ting Feng
Described herein is a facile and efficient methodology toward the synthesis of Morusin scaffolds and Morusignin L scaffolds 4-9 and 12via a novel three-step approach (Michael addition or prenylation, cyclization and cyclization) and use a rapid, microwave-accelerated cyclization as the key step. Furthermore, their biological activities have been preliminarily demonstrated by in vitro evaluation for anti-osteoporosis activity. These Morusin, Morusignin L and newly synthesized compounds 5b, 6a, 8e, 8f greatly exhibited the highest potency, especially at the 10(-5)mol/L (P<0...
April 9, 2017: Bioorganic & Medicinal Chemistry Letters
Yan Xu, Zu Wang, Chunhui Li, Kuo-Chen Chou
PURPOSE: Occurring at the cysteine residue in the C-terminal of a protein, prenylation is a special kind of post-translational modification (PTM), which may play a key role for statin in altering immune function. Therefore, knowledge of the prenylation sites in proteins is important for drug development as well as for in-depth understanding the biological process concerned. Given a query protein whose C-terminal contains some cysteine residues, which one can be of prenylation or none of them can be prenylated? METHODS: To address this problem, we have developed a new predictor, called "iPreny-PseAAC", by incorporating two tiers of sequence pair coupling effects into the general form of PseAAC (pseudo amino acid composition)...
April 19, 2017: Medicinal Chemistry
Elena Ciaglia, Manuela Grimaldi, Mario Abate, Mario Scrima, Manuela Rodriquez, Chiara Laezza, Roberta Ranieri, Simona Pisanti, Pierangela Ciuffreda, Clementina Manera, Patrizia Gazzerro, Anna Maria D'Ursi, Maurizio Bifulco
BACKGROUND AND PURPOSE: N6-Isopentenyladenosine (i6A) is a modified nucleoside exerting in vitro and in vivo antiproliferative effects. We previously demonstrated that the i6A action is correlated to farnesyl pyrophosphate synthase (FPPS) expression and activity, a key enzyme involved in the mevalonate (MVA) pathway, which is found aberrant in brain cancer. To develop new anti-glioma strategies, we looked for other valuable compounds exhibiting improved activity as compared to i6A. EXPERIMENTAL APPROACH: we designed and synthesized i6A derivatives characterized by the introduction of diverse chemical moieties in the N6 position of adenosine and tested for their efficacy in U87 and primary derived patient's glioma cell model...
April 18, 2017: British Journal of Pharmacology
Florence M Schempp, Laura Drummond, Markus Buchhaupt, Jens Schrader
Terpenoid flavor and fragrance compounds are of high interest to the aroma industry. Microbial production offers an alternative sustainable access to the desired terpenoids independent of natural sources. Genetically engineered microorganisms can be used to synthesize terpenoids from cheap and renewable resources. Due to its modular architecture, terpenoid biosynthesis is especially well suited for the microbial cell factory concept: a platform host engineered for a high flux toward the central C5 prenyl diphosphate precursors enables the production of a broad range of target terpenoids just by varying the pathway modules converting the C5 intermediates to the product of interest...
April 18, 2017: Journal of Agricultural and Food Chemistry
Qing-Hui Wang, Shuai Guo, Xue-Yan Yang, Yi-Fan Zhang, Ming-Ying Shang, Ying-Hui Shang, Jun-Jun Xiao, Shao-Qing Cai
Four prenylated flavonoids compounds 1-4, named sinopodophyllines A-D, and a flavonoid glycoside (compound 13), sinopodophylliside A, together with 19 known compounds (compounds 5-12 and 14-24) were isolated from the fruits of Sinopodophyllum hexandrum. The structures of new compounds were elucidated by extensive spectroscopic analysis, including HRESIMS, 1D and 2D NMR. Compounds 1-6, 9-11, and 14-17 were tested for their cytotoxicity against human breast-cancer T47D, MCF-7 and MDA-MB-231 cells in vitro, and compounds 2, 5, 6, 10 and 11 showed significant cytotoxicity (IC50 values < 10 μmol·L(-1)) against T47D cells...
March 2017: Chinese Journal of Natural Medicines
Yuan Li, Ze-Hong Wu, Ke-Wu Zeng, Ming-Bo Zhao, Yong Jiang, Jun Li, Peng-Fei Tu
A new prenylated flavone, 3,5,7,3'-tetrahydroxy-8,4'-dimethoxy-6-(3-methylbut-2- enyl)flavone (1), together with three known flavone derivatives (2-4), two known dihydrophenanthrenes (5-6), two known lignin derivatives (7-8), and three known phenolic glycoside compounds (9-11) were isolated from the n-BuOH extract of Pleione bulbocodioides. High-resolution electrospray ionization mass spectroscopy (HRESIMS), FTIR spectroscopy, and NMR techniques were used to elucidate the structures of these compounds. Biological investigations showed that compound 5, 4,7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene, exhibited potent anti-inflammatory activity on LPS-stimulated NO production in BV-2 microglial cells, with IC50 value of 5...
April 12, 2017: Journal of Asian Natural Products Research
Bernd Schmidt, Felix Wolf
The Pd-catalyzed Heck-type coupling (Matsuda-Heck reaction) of electron rich arene diazonium salts with electron deficient olefins has been exploited for the synthesis of phenylpropanoid natural products. Examples described herein are the naturally occurring benzofurans methyl wutaifuranate, wutaifuranol, wutaifuranal, their 7-methoxy derivatives, and the O-prenylated natural products boropinols A and C.
April 13, 2017: Journal of Organic Chemistry
Chang-Xin Zhou, Yu-E Yu, Rong Sheng, Jian-Xia Mo, Min Huang, Liang Ouyang, Lishe Gan
Two dimeric prenylindole alkaloids with an unique indole-benzoindolequinone skeleton, cimicifoetones A (1) and B (2), were isolated as black pigments from the rhizomes of Cimicifuga foetida. The structures were elucidated by spectroscopic methods including HRMS and 2D NMR, as well as single crystal X-ray diffraction and computational chemical modeling techniques. Cimicifoetones A and B represented the first examples of dimeric indole alkaloids generated through [4+2] Diels-Alder cycloaddition between the prenyl side chain in one 3-prenylindole and the aromatic ring in another...
April 9, 2017: Chemistry, An Asian Journal
Naohiko Kinoshita, Akira Matsuura, Yukio Fujiki
Pex19p harbouring a prenylation CAAX box functions as a chaperone and transporter for peroxisomal membrane proteins in membrane assembly. By functional phenotype-complementation assay using a pex19 Chinese hamster ovary cell mutant ZP119, we herein cloned a rat cDNA encoding a protein similar to Pex19p, but with a C-terminal hydrophobic segment in place of the CAAX box region. The transcript of this gene was highly induced by treatment of rats with a peroxisome proliferator, clofibrate, hence termed PEX19i, while the other three less prominently inducible PEX19 variants encoded authentic Pex19p but differed in the length of 3' non-coding region...
March 1, 2017: Journal of Biochemistry
Yang Chen, Jianping Zhao, Yixing Qiu, Hanwen Yuan, Shabana I Khan, Nusrat Hussain, M Iqbal Choudhary, Feng Zeng, De-An Guo, Ikhlas A Khan, Wei Wang
Phytochemical investigation on the stems and roots of Tripterygium wilfordii led to the isolation and characterization of three new prenylated flavanones, tripteryols A-C (1-3), along with (±)-5,4'-dihydroxy-2'-methoxy-6',6″-dimethypyraro-(2″,3″:7,8)-6-methyflavanone (4), and ((2S)-5,7,4'-trihydroxy-2'-methoxy-8,5'-di(3-methyl-2-butenyl)-6-methylflavanone (5). Structures of the compounds 1-5 were elucidated using spectroscopic techniques, such as UV, IR, NMR (1D and 2D), and HRESI-MS. Tripteryols B (2) was found active in the antimicrobial assay against Cryptococcus neoformans, Pseudomonas aeruginosa, vancomycin-resistant Enterococcus faecalis (VRE) and methicillin-resistant Staphylococcus aureus (MRSA) with IC50 values in the range of 2...
April 5, 2017: Fitoterapia
Johanna M Jansen, Charles Wartchow, Wolfgang Jahnke, Susan Fong, Tiffany Tsang, Keith Pfister, Tatiana Zavorotinskaya, Dirksen Bussiere, Jan Marie Cheng, Kenneth Crawford, Yumin Dai, Jeffrey Dove, Eric Fang, Yun Feng, Jean-Michel Florent, John Fuller, Alvar D Gossert, Mohammad Hekmat-Nejad, Chrystèle Henry, Julia Klopp, William P Lenahan, Andreas Lingel, Sylvia Ma, Arndt Meyer, Yuji Mishina, Jamie Narberes, Gwynn Pardee, Savithri Ramurthy, Sebastien Rieffel, Darrin Stuart, Sharadha Subramanian, Laura Tandeske, Stephania Widger, Armin Widmer, Aurelie Winterhalter, Isabel Zaror, Stephen Hardy
RAS mutations lead to a constitutively active oncogenic protein that signals through multiple effector pathways. In this chemical biology study, we describe a novel coupled biochemical assay that measures activation of the effector BRAF by prenylated KRASG12V in a lipid-dependent manner. Using this assay, we discovered compounds that block biochemical and cellular functions of KRASG12V with low single-digit micromolar potency. We characterized the structural basis for inhibition using NMR methods and showed that the compounds stabilized the inactive conformation of KRASG12V...
2017: PloS One
Jitka Frébortová, Ondřej Plíhal, Vendula Florová, Filip Kokáš, Karolina Kubiasová, Marta Greplová, Jan Šimura, Ondřej Novák, Ivo Frébort
Cytokinins are an important group of plant hormones that are also found in other organisms, including cyanobacteria. While various aspects of cytokinin function and metabolism are well understood in plants, the information is limited for cyanobacteria. In this study, we first experimentally confirmed a prenylation of tRNA by recombinant isopentenyl transferase NoIPT2 from Nostoc sp. PCC 7120, whose encoding gene we previously identified in Nostoc genome along with the gene for adenylate isopentenyl transferase NoIPT1...
April 4, 2017: Journal of Phycology
Junji Terao
Nowadays dietary flavonoids attract much attention in the prevention of chronic diseases. Epidemiological and intervention studies strongly suggest that flavonoid intake has beneficial effects on vascular health. It is unlikely that flavonoids act as direct antioxidants, although oxidative stress profoundly contributes to vascular impairment leading to cardiovascular diseases. Instead, flavonoids may exert their function by tuning the cellular redox state to an adaptive response or tolerable stress. However, the optimum intake of flavonoids from supplements or diet has not been clarified yet, because a number of exogenous and endogenous factors modulating their bioavailability affect their vascular function...
April 2, 2017: Biochemical Pharmacology
Qian Sun, Guo-Dong Yao, Xiao-Yu Song, Xiao-Li Qi, Yu-Fei Xi, Ling-Zhi Li, Xiao-Xiao Huang, Shao-Jiang Song
Enantiomers account for quite a large percentage of compounds in natural products. Our team is interested in the separation and biological activity of racemic compounds. In this report, four pairs of prenylated flavan enantiomers [(±)-1-(±)-4], including five new compounds, were isolated from the stem and root bark of Daphne giraldii, and separated successfully by using chiral chromatographic column. Their planar structures and absolute configurations were established by comprehensive spectroscopic analyses as well as circular dichroism (CD) spectroscopy...
March 30, 2017: European Journal of Medicinal Chemistry
Paola Maura Tricarico, Alessandra Romeo, Rossella Gratton, Sergio Crovella, Fulvio Celsi
BACKGROUND/AIMS: Mevalonate Kinase Deficiency (MKD), is a hereditary disease due to mutations in mevalonate kinase gene (MVK). MKD has heterogeneous clinical phenotypes: the correlation between MVK mutations and MKD clinical phenotype is still to be fully elucidated. Deficiency of prenylated proteins has been hypothesized as possible MKD pathogenic mechanism. Based on this hypothesis and considering that neurologic impairment characterizes Mevalonic Aciduria (MA), the most severe form of MKD, we studied the effects of I268T and N301T MVK mutations on protein prenylation, autophagy and programmed cell death in SH-SY5Y neuroblastoma cell lines...
March 28, 2017: Cellular Physiology and Biochemistry
Imaobong Christopher Etti, Abdullah Rasedee, Najihah Mohd Hashim, Ahmad Bustamam Abdul, Arifah Kadir, Swee Keong Yeap, Peter Waziri, Ibrahim Malami, Kian Lam Lim, Christopher J Etti
Artonin E is a prenylated flavonoid compound isolated from the stem bark of Artocarpus elasticus. This phytochemical has been previously reported to be drug-like with full compliance to Lipinski's rule of five and good physicochemical properties when compared with 95% of orally available drugs. It has also been shown to possess unique medicinal properties that can be utilized in view of alleviating most human disease conditions. In this study, we investigated the cytotoxic mechanism of Artonin E in MCF-7 breast cancer cells, which has so far not been reported...
2017: Drug Design, Development and Therapy
Carla Araya-Cloutier, Bianca Martens, Gijs Schaftenaar, Franziska Leipoldt, Harry Gruppen, Jean-Paul Vincken
Acceptor substrate specificity of Streptomyces roseochromogenes prenyltransferase SrCloQ was investigated using different non-genuine phenolic compounds. RP-UHPLC-UV-MSn was used for the tentative annotation and quantification of the prenylated products. Flavonoids, isoflavonoids and stilbenoids with different types of substitution were prenylated by SrCloQ, although with less efficiency than the genuine substrate 4-hydroxyphenylpyruvate. The isoflavan equol, followed by the flavone 7,4'-dihydroxyflavone, were the best non-genuine acceptor substrates...
2017: PloS One
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