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Christopher J Schwalen, Xinxin Feng, Weidong Liu, Bing O-Dowd, Tzu-Ping Ko, Christopher J Shin, Rey-Ting Guo, Douglas A Mitchell, Eric Oldfield
Many organisms contain "head-to-head" isoprenoid synthases and here, we investigate three types of such enzymes from the pathogens Neisseria meningitidis, N. gonorrhoeae, and Enterococcus hirae. The E. hirae enzyme was found to produce dehydrosqualene and we solved an inhibitor-bound structure which revealed a fold similar to that of CrtM from Staphylococcus aureus. In contrast, the homologous proteins from Neisseria spp. carried out only the "first half" reaction, yielding presqualene diphosphate (PSPP). Based on product analyses, bioinformatics, and mutagenesis we conclude that the Neisseria proteins are HpnDs (PSPP synthases)...
March 24, 2017: Chembiochem: a European Journal of Chemical Biology
Hui Ding, Wanjing Ding, Zhongjun Ma
Two prenylated indole alkaloids were isolated from the ethyl acetate extracts of a marine-derived fungus Penicillium sp. NH-SL and one of them exhibited potent cytotoxic activity against mouse hepa 1c1c7 cells. In order to detect other bioactive analogs, we used liquid chromatogram tandem mass spectrometry (LC-MS/MS) to analyze the mass spectrometric characteristics of the isolated compounds as well as the crude extracts. As a result, three other analogs were detected, and their structures were deduced according to the similar fragmentation patterns...
March 22, 2017: Marine Drugs
Xue Fei Tan, Zia Uddin, Chanin Park, Yeong Hun Song, Minky Son, Keun Woo Lee, Ki Hun Park
Protein tyrosine phosphatase 1B (PTP1B) plays important role in diabetes, obesity and cancer. The methanol extract of the gum resin of Garcinia hanburyi (G. hanburyi) showed potent PTP1B inhibition at 10µg/ml. The active compounds were identified as prenylated caged xanthones (1-9) which inhibited PTP1B in dose-dependent manner. Carboxybutenyl group within caged motif (A ring) was found to play a critical role in enzyme inhibition such as 1-6 (IC50s=0.47-4.69µM), whereas compounds having hydroxymethylbutenyl 7 (IC50=70...
March 6, 2017: Bioorganic & Medicinal Chemistry
Birgit Arndt, Slavica Janevska, Robin Schmid, Florian Hübner, Bettina Tudzynski, Hans-Ulrich Humpf
The range of secondary metabolites (SMs) produced by the rice pathogen Fusarium fujikuroi is quite broad. Several polyketides, nonribosomal peptides and terpenes have been identified. However, no products of dimethylallyltryptophan synthases (DMATSs) have been elucidated so far, though two putative DMATS genes are present in the F. fujikuroi genome. In this study, the product derived from one of the two DMATSs, DMATS1 (FFUJ_09179), has been identified in vivo with the help of the software MZmine 2. Detailed structure elucidation showed that this metabolite is a reversely N-prenylated tryptophan, depicting a rather rare form of prenylation...
March 10, 2017: Chembiochem: a European Journal of Chemical Biology
Heike E Weber, Manuela Gottardi, Christine Brückner, Mislav Oreb, Eckhard Boles, Joanna Tripp
Biotechnological production of cis, cis-muconic acid from renewable feedstocks is an environmentally sustainable alternative to conventional, petroleum-based methods. Even though a heterologous production pathway for cis, cis-muconic acid has already been established in the host organism Saccharomyces cerevisiae, the generation of industrially relevant amounts of cis, cis-muconic acid is hampered by the low activity of the bacterial protocatechuic acid (PCA) decarboxylase AroY subunit C(iso) (AroY-C(iso)), leading to secretion of high amounts of the intermediate PCA to the medium...
March 10, 2017: Applied and Environmental Microbiology
Yuankun Zhai, Yingying Li, Yanping Wang, Jiawei Cui, Kun Feng, Xijian Kong, Li Chen
Traditional Chinese medicines (TCM) have been proven to prevent osteoporosis, but their clinical applications are not widely recognized due to their complicated ingredients. Psoralidin, a prenylated coumestan, has been reported to prevent bone loss of ovariectomized rats, but detailed mechanisms are still not clear. In current study, we found that both psoralidin and coumestrol promoted osteoblast proliferation and differentiation, as evidenced by improvements in cell proliferation and alkaline phosphatase activity; increased formation of ALP colonies and calcified nodules; enhanced secretion of collagen-I, BMP-2, osteocalcin and osteopontin; and stimulation of the expression of IGF-1, β-catenin, Runx-2, Osterix, and OPG, as well as the mRNA ratio of OPG/RANKL, while significantly decreasing the expression of RANKL...
March 8, 2017: European Journal of Pharmacology
Zohreh Jelodarian, Yalda Shokoohinia, Maryam Rashidi, Nastaran Ghiasvand, Leila Hosseinzadeh, Mehrdad Iranshahi
Echinophora cinerea aerial parts are used in folk medicine to cure gastric diseases and as a food seasoning in cheese and yogurt. Besides several pharmacological effects have been assigned to Echinophora spp., there is no phytochemical investigation on this genus other than our previous publication on flavonoids. An acetone extract of E. cinerea afforded three new (1-3) polyacetylenes, one rare monoterpenoid glycoside as verbenone-5-O-β-D-glycopyranoside (4) and one prenylated coumarin as osthol (5). The structures of all new compounds were elucidated using modern spectroscopic methods, including 2D NMR and mass analyses...
March 10, 2017: Natural Product Research
Ruchika Bhardwaj, Mousumi Das, Shalini Singh, Adarsh Kumar Chiranjivi, Sitraraau Vijaya Prabhu, Sanjeev Kumar Singh, Vikash Kumar Dubey
Prenylation pathway is responsible for post translational modification of various signal proteins, including proteins of Ras superfamily. CAAX prenyl proteases are known to be key players in prenylation pathway. In the current study, we have evaluated CAAX prenyl protease II as a possible drug target against Leishmania donovani parasite, the causative agent of visceral leishmaniasis. Gene knockout strategy was employed to target CAAX prenyl protease II and subsequent effects were studied. CAAX prenyl protease II knockout resulted in significant decrease in growth and infectivity...
March 7, 2017: European Journal of Pharmaceutical Sciences
María D Santi, Mariana A Peralta, Caterine S Mendoza, José Luis Cabrera, María G Ortega
Two new prenylated flavanones, pazentin A (3',4'-dihydroxy-6,2'-diprenylpinocembrin, 1) and pazentin B [4'-hydroxy-2'-methoxy-5'-(1‴, 1‴-dimethylallyl)-6-prenylpinocembrin, 2] together with two known ones (3 and 4) previously isolated from other Dalea species were obtained from the benzene extract of Dalea pazensis Rusby roots. The compounds were evaluated in vitro for their inhibition on mushroom tyrosinase enzyme and in relation to their effect on melanogenesis in B16 murine melanoma cells, by using a spectrophotometric method...
February 27, 2017: Bioorganic & Medicinal Chemistry Letters
Zhemin Li, Genhai Zhao, Hui Liu, Yugang Guo, Hefang Wu, Xiaowen Sun, Xihua Wu, Zhiming Zheng
Prenylated quinones, especially menaquinones, have significant physiological activities, but are arduous to synthesize efficiently. Due to the relaxed aromatic substrate specificity and prenylation regiospecificity at the ortho- site of the phenolic hydroxyl group, the aromatic prenyltransferase NovQ from Streptomyces may be useful in menaquinone synthesis from menadione. In this study, NovQ was overexpressed in Pichia pastoris. After fermentation optimization, NovQ production increased by 1617%. Then the different effects of metal ions, detergents and pH on the activity of purified NovQ were investigated to optimize the prenylation reaction...
March 3, 2017: Journal of Industrial Microbiology & Biotechnology
Li Liu, Long Wang, Li Bao, Jinwei Ren, Buddha Bahadur Basnet, Ruixing Liu, Luwei He, Junjie Han, Wen-Bing Yin, Hongwei Liu
No abstract text is available yet for this article.
March 3, 2017: Organic Letters
Carla Araya-Cloutier, Heidy M W den Besten, Siti Aisyah, Harry Gruppen, Jean-Paul Vincken
The legume plant family (Fabaceae) is a potential source of antimicrobial phytochemicals. Molecular diversity in phytochemicals of legume extracts was enhanced by germination and fungal elicitation of seven legume species, as established by RP-UHPLC-UV-MS. The relationship between phytochemical composition, including different types of skeletons and substitutions, and antibacterial properties of extracts was investigated. Extracts rich in prenylated isoflavonoids and stilbenoids showed potent antibacterial activity against Listeria monocytogenes and methicillin-resistant Staphylococcus aureus at concentrations between 0...
July 1, 2017: Food Chemistry
Yang Hee Jo, Seon Beom Kim, Qing Liu, Seon-Gil Do, Bang Yeon Hwang, Mi Kyeong Lee
The composition and content of the active constituents and their biological activity vary according to diverse factors including their maturation stages. A previous study showed that the fruits of Cudrania tricuspidata inhibited pancreatic lipase activity, a key enzyme in fat absorption. In this study, we investigated the chemical composition and pancreatic lipase inhibitory activity of unripe and ripe fruits of C. tricuspidata. Unripe fruits of C. tricuspidata have a higher content of total phenolic and flavonoids and exhibited stronger pancreatic lipase inhibition compared to ripe fruits...
2017: PloS One
Pan Sun, Chang-Sheng Jiang, Yi Zhang, Ai-Hong Liu, Tong-Jun Liang, Jia Li, Yue-Wei Guo, Jian-Mei Jiang, Shui-Chun Mao, Bin Wang
Four new prenylated bibenzyls, named aglaiabbrevins A-D (2, 4-6), were isolated from the leaves of Aglaia abbreviata, along with two known related analogues, 3,5-dihydroxy-2-[3,7-dimethyl-2(E),6-octadienyl]bibenzyl (7) and 3,5-dihydroxy-2-(3-methyl-2-butenyl)bibenzyl (8). The structures of the new compounds were elucidated on the basis of extensive spectroscopic experiments, mainly one and two dimensional (1D- and 2D)-NMR, and the absolute configuration of 5 was determined by the measurement of specific rotation...
2017: Chemical & Pharmaceutical Bulletin
Alexandra Svouraki, Ulrike Garscha, Eirini Kouloura, Simona Pace, Carlo Pergola, Verena Krauth, Antonietta Rossi, Lidia Sautebin, Maria Halabalaki, Oliver Werz, Nicolas Gaboriaud-Kolar, Alexios-Leandros Skaltsounis
Among the pathways responsible for the development of inflammatory responses, the cyclooxygenase and lipoxygenase pathways are among the most important ones. Two key enzymes, namely, 5-LO and mPGES-1, are involved in the biosynthesis of leukotrienes and prostaglandins, respectively, which are considered attractive therapeutic targets, so their dual inhibition might be an effective strategy to control inflammatory deregulation. Several natural products have been identified as 5-LO inhibitors, with some also being dual 5-LO/mPGES-1 inhibitors...
February 27, 2017: Journal of Natural Products
Shu-Shan Gao, Marc Garcia-Borràs, Joyann S Barber, Yang Hai, Abing Duan, Neil K Garg, K N Houk, Yi Tang
Hydroalkoxylation is a powerful and efficient method of forming C-O bonds and cyclic ethers in synthetic chemistry. In studying the biosynthesis of the fungal natural product herqueinone, we identified an enzyme that can perform an intramolecular enantioselective hydroalkoxylation reaction. PhnH catalyzes the addition of a phenol to the terminal olefin of a reverse prenyl group to give a dihydrobenzofuran product. The enzyme accelerates the reaction by 3 × 10(5)-fold compared to the uncatalyzed reaction. PhnH belongs to a superfamily of proteins with a domain of unknown function (DUF3237), of which no member has a previously verified function...
March 15, 2017: Journal of the American Chemical Society
Mohanad H Nada, Hong Wang, Grefachew Workalemahu, Yoshimasa Tanaka, Craig T Morita
BACKGROUND: Human γδ T cells expressing Vγ2Vδ2 T cell receptors monitor foreign- and self-prenyl pyrophosphate metabolites in isoprenoid biosynthesis to mediate immunity to microbes and tumors. Adoptive immunotherapy with Vγ2Vδ2 T cells has been used to treat cancer patients with partial and complete remissions. Most clinical trials and preclinical studies have used continuous zoledronate exposure to expand Vγ2Vδ2 cells where zoledronate is slowly diluted over the course of the culture...
2017: Journal for Immunotherapy of Cancer
Matthew Rees, Nigel S Simpkins, Louise Male
Michael addition of a proline-derived triketopiperazine (TKP) to β-substituted enones and acrylamides, mediated by a cinchona alkaloid catalyst, delivers products possessing a bicyclo[2.2.2]diazaoctane structure in high yield and enantiomeric ratio (er). Further modification of the amide products toward polycyclic scaffolds resembling members of the prenylated alkaloid family is also demonstrated.
February 23, 2017: Organic Letters
Katja Backhaus, Lena Ludwig-Radtke, Xiulan Xie, Shu-Ming Li
The tryptophan derivative 1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid (MTCA) is present in many plants and foods including fermentation products of the baker's yeast Saccharomyces cerevisiae. MTCA is formed from tryptophan and acetaldehyde via a Pictet-Spengler reaction. In this study, up to 9 mg/L of MTCA were detected as a mixture of (1S,3S) and (1R,3S) isomers in a ratio of 2.2:1 in Saccharomyces cerevisiae cultures. To the best of our knowledge, this is the first report on the presence of MTCA in laboratory baker's yeast cultures...
March 2, 2017: ACS Synthetic Biology
Fei Liu, Yayun Qin, Shanshan Yu, Dinesh C Soares, Lifang Yang, Jun Weng, Chang Li, Meng Gao, Zhaojing Lu, Xuebin Hu, Xiliang Liu, Tao Jiang, Jing Y Liu, Xinhua Shu, Zhaohui Tang, Mugen Liu
Mutations in retinitis pigmentosa 2 (RP2) account for 10-20% of X-linked retinitis pigmentosa (RP) cases. The encoded RP2 protein is implicated in ciliary trafficking of myristoylated and prenylated proteins in photoreceptor cells. To date, over 70 mutations in RP2 have been identified. How these mutations disrupt the function of RP2 is not fully understood. Here, we report a novel in-frame 12-bp deletion (c.357_368del, p.Pro120_Gly123del) in zebrafish rp2 The mutant zebrafish shows reduced rod phototransduction proteins and progressive retinal degeneration...
February 16, 2017: Journal of Biological Chemistry
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