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Takahiro Sawada, Miho Eguchi, Seiya Asaki, Ryota Kashiwagi, Kousuke Shimomura, Fumiko Taguchi, Hidenori Matsui, Mikihiro Yamamoto, Yoshiteru Noutoshi, Kazuhiro Toyoda, Yuki Ichinose
Our previous studies revealed that flagellar-motility-defective mutants such as ∆fliC of Pseudomonas syringae pv. tabaci 6605 (Pta6605) have remarkably reduced production of N-acyl-homoserine lactones (AHL), quorum-sensing molecules. To investigate the reason of loss of AHL production in ∆fliC mutant, we carried out transposon mutagenesis. Among approximately 14,000 transconjugants, we found 11 AHL production-recovered (APR) strains. In these APR strains, a transposon was inserted into either mexE or mexF, genes encoding for the multidrug efflux pump transporter MexEF-OprN, and mexT, a gene encoding a putative transcriptional activator for mexEF-oprN...
March 16, 2018: Molecular Genetics and Genomics: MGG
Prama Pallavi, Marc Pretze, Julio Caballero, Yingchun Li, Björn B Hofmann, Eleni Stamellou, Sarah Klotz, Carmen Wängler, Björn Wängler, Ralf Loesel, Steffen Roth, Bastian Theisinger, Handan Moerz, Uta Binzen, Wolfgang Greffrath, Rolf-Detlef Treede, Martin C Harmsen, Bernhard K Krämer, Mathias Hafner, Benito A Yard, Anna-Isabelle Kälsch
We studied the chemical entities within N-octanoyl dopamine (NOD) responsible for transient receptor potential channels of the vanilloid receptor subtype 1 (TRPV1) activation and inhibition of inflammation. The efficacy of NOD to activate TRPV1 was significantly higher compared to variants in which the ortho-dihydroxy groups were acetylated, one of the hydroxy groups was omitted (N-octanoyl tyramine) or the ester functionality consisted of a bulky fatty acid (N-pivaloyl dopamine). Shortening of the amide linker (ΔNOD) slightly increased its efficacy which further increased by interchanging the carbonyl and amide groups (ΔNODR)...
March 15, 2018: Journal of Medicinal Chemistry
R Bonsale, R Seyed Sharifi, E Dirandeh, N Hedayat, A Mojtahedin, M Ghorbanalinia, A Abolghasemi
The objective of this study was to consider endocannabinoid system as inflammatory markers in bovine endometrium to better understand the role of this system in regulating many of the functions that are related to inflammatory condition. At day 26 post-partum, fourteen cows were divided into two groups depending on the inflammatory condition: 1- subclinical endometritis (n = 7, with purulent or mucopurulent uterine discharge detectable in the vagina) and 2- healthy (n = 7, No (muco)) purulent discharge...
March 14, 2018: Reproduction in Domestic Animals, Zuchthygiene
Hua Lin, Jonathan Z Long, Alexander M Roche, Katrin J Svensson, Florence Dou, Mi Ra Chang, Timothy Strutzenberg, Claudia Ruiz, Michael D Cameron, Scott J Novick, Charles M Berdan, Sharon Louie, Daniel K Nomura, Bruce M Spiegelman, Patrick R Griffin, Theodore M Kamenecka
N-acyl amino acids directly bind mitochondria and function as endogenous uncouplers of UCP1-independent respiration. We found that administration of N-acyl amino acids to mice improves glucose homeostasis and increases energy expenditure indicating that this pathway might be useful for treating obesity and associated disorders. We report the full account of the synthesis and mitochondrial uncoupling bioactivity of lipidated N-acyl amino acids and their unnatural analogs. Unsaturated fatty acid chains of medium length and neutral amino acid head groups are required for optimal uncoupling activity on mammalian cells...
March 13, 2018: Journal of Medicinal Chemistry
So-Young Ham, Han-Shin Kim, Eunji Cha, Jeong-Hoon Park, Hee-Deung Park
In this study, a quorum-quenching (QQ) bacterium named HEMM-1 was isolated at a membrane bioreactor (MBR) plant. HEMM-1 has diplococcal morphology and 99% sequence identity to Enterococcus species. The HEMM-1 cell-free supernatant (CFS) showed higher QQ activities than the CFS of other QQ bacteria, mostly by degrading N-acyl homoserine lactones (AHLs) with short acyl chains. Instrumental analyses revealed that HEMM-1 CFS degraded AHLs via lactonase activity. Under static, flow, and shear conditions, the HEMM-1 CFS was effective in reducing bacterial and activated-sludge biofilms formed on membrane surfaces...
March 2, 2018: Bioresource Technology
Sujith Rajan, Sabbu Satish, Kripa Shankar, Sukanya Pandeti, Salil Varshney, Ankita Srivastava, Durgesh Kumar, Abhishek Gupta, Sanchita Gupta, Rakhi Choudhary, Vishal M Balaramnavar, Tadigoppula Narender, Anil N Gaikwad
BACKGROUND AND PURPOSE: In our drug discovery program of natural product, earlier we have reported Aegeline that is N-acylated-1-amino-2- alcohol, which was isolated from the leaves of Aeglemarmelos showed anti-hyperlipidemic activity for which the QSAR studies predicted the compound to be the β3-AR agonist, but the mechanism of its action was not elucidated. In our present study, we have evaluated the β3-AR activity of novel N-acyl-1-amino-3-arylopropanol synthetic mimics of aegeline and its beneficial effect in insulin resistance...
March 7, 2018: Metabolism: Clinical and Experimental
Pratheepkumar Annamalai, Kou-Chi Hsu, Selvam Raju, Huan-Chang Hsiao, Chih-Wei Chou, Gu-Ying Lin, Cheng-Ming Hsieh, Pei-Ling Chen, Yi-Hung Liu, Shih-Ching Chuang
We developed palladium-catalyzed oxidative coupling of olefins with N-acyl 2-aminobiaryls through a sequence of ortho C-H bond activation/alkene insertion/reductive elimination. Furthermore, we controlled the selectivity of mono- and bis-alkenylation products with the solvent effect. The developed protocol was promising for a broad substrate scope ranging from activated olefins with a wide variety of functional groups to unactivated olefins.
March 9, 2018: Journal of Organic Chemistry
Gael Pérez-Rodríguez, Sónia Dias, Martín Pérez-Pérez, Florentino Fdez-Riverola, Nuno F Azevedo, Anália Lourenço
Experimental incapacity to track microbe-microbe interactions in structures like biofilms, and the complexity inherent to the mathematical modelling of those interactions, raises the need for feasible, alternative modelling approaches. This work proposes an agent-based representation of the diffusion of N-acyl homoserine lactones (AHL) in a multicellular environment formed by Pseudomonas aeruginosa and Candida albicans. Depending on the spatial location, C. albicans cells were variably exposed to AHLs, an observation that might help explain why phenotypic switching of individual cells in biofilms occurred at different time points...
March 8, 2018: Biofouling
Servane Le Guillouzer, Marie-Christine Groleau, Eric Déziel
The bacterium Burkholderia thailandensis possesses three N -acyl-L -homoserine lactone (AHL) quorum sensing (QS) systems designated BtaI1/BtaR1 (QS-1), BtaI2/BtaR2 (QS-2), and BtaI3/BtaR3 (QS-3). These QS systems are associated with the biosynthesis of N -octanoyl-homoserine lactone (C8 -HSL), N -3-hydroxy-decanoyl-homoserine lactone (3OHC10 -HSL), and N -3-hydroxy-octanoyl-homoserine lactone (3OHC8 -HSL), which are produced by the LuxI-type synthases BtaI1, BtaI2, and BtaI3, and modulated by the LuxR-type transcriptional regulators BtaR1, BtaR2, and BtaR3...
March 5, 2018: Journal of Bacteriology
Yi Du, Yunyun Liu, Jie-Ping Wan
The synthesis of N-acyl-5-halo-8-aminoquinolines has been realized by directly employing 8-aminoquinolines and acyl halides (Cl, Br, I) with copper catalysis. The construction of the target products involves in the domino N-acylation and C5-H halogenations of the 8-aminoquinoline wherein the acyl halides act as the donors of both acyl and halide atom, which enables the first access to the step efficient synthesis of 5-halogenated N-acyl quinlolines from commercial 8-aminoquinolines.
March 2, 2018: Journal of Organic Chemistry
Rosana Leiva, Andrew McBride, Margaret Binnie, Scott P Webster, Santiago Vázquez
We recently found that a cyclohexanecarboxamide derived from 4-azatetracyclo[,6 .08,10 ]dodec-11-ene displayed low nanomolar inhibition of 11β-HSD1. In continuation of our efforts to discover potent and selective 11β-HSD1 inhibitors, herein we explored several replacements for the cyclohexane ring. Some derivatives exhibited potent inhibitory activity against human 11β-HSD1, although with low selectivity over the isoenzyme 11β-HSD2, and poor microsomal stability.
February 28, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Cesar Gonzalez, Andersson Sanchez, Jeffrey Collins, Ksenia Lisova, Jason T Lee, R Michael van Dam, M Alejandro Barbieri, Cheppail Ramachandran, Stanislaw F Wnuk
The coupling of gemcitabine with functionalized carboxylic acids using peptide coupling conditions afforded 4-N-alkanoyl analogues with a terminal alkyne or azido moiety. Reaction of 4-N-tosylgemcitabine with azidoalkyl amine provided 4-N-alkyl gemcitabine with a terminal azido group. Click reaction with silane building blocks afforded 4-N-alkanoyl or 4-N-alkyl gemcitabine analogues suitable for fluorination. RP-HPLC analysis indicated better chemical stability of 4-N-alkyl gemcitabine analogues versus 4-N-alkanoyl analogues in acidic aqueous conditions...
February 12, 2018: European Journal of Medicinal Chemistry
Andrea Muras, Mario López-Pérez, Celia Mayer, Ana Parga, Jaime Amaro-Blanco, Ana Otero
There is increasing evidence being accumulated regarding the importance of N -acyl homoserine lactones (AHL)-mediated quorum-sensing (QS) and quorum-quenching (QQ) processes in the marine environment, but in most cases, data has been obtained from specific microhabitats, and subsequently little is known regarding these activities in free-living marine bacteria. The QS and QQ activities among 605 bacterial isolates obtained at 90 and 2000 m depths in the Mediterranean Sea were analyzed. Additionally, putative QS and QQ sequences were searched in metagenomic data obtained at different depths (15-2000 m) at the same sampling site...
February 16, 2018: Genes
Cosima Damiana Calvano, Marco Glaciale, Francesco Palmisano, Tommaso R I Cataldi
Hydrophilic interaction liquid chromatography coupled to negative-ion electrospray linear ion-trap multiple-stage mass spectrometry (HILIC-ESI-MSn , n = 2,3) was used to characterize polar lipids occurring in donkey milk. Besides the detection of abundant phospholipids, the structural characterization and content evaluation of minor glycosphingolipids (GSL) was assessed. We report an unprecedented characterization of 11 hexosyl-ceramides (HexCer), 10 Hex2 Cer and 4 Hex3 Cer. Collision-induced dissociation (CID-MS/MS) spectra in negative ion mode mainly afford information on the monosaccharide number and ceramide constitution (i...
February 20, 2018: Electrophoresis
Naoki Teno, Yukiko Yamashita, Yusuke Iguchi, Ko Fujimori, Mizuho Une, Tomoko Nishimaki-Mogami, Takie Hiramoto, Keigo Gohda
Farnesoid X receptor (FXR) plays a major role in the control of cholesterol metabolism. Antagonizing transcriptional activity of FXR is an effective means to treat the relevant metabolic syndrome. Some of antagonists so far have the charged functions; however, they may negatively affect the pharmacokinetics. We describe herein a structure-activity relationship (SAR) exploration of nonacidic FXR antagonist 6 focusing on two regions in the structure and biological evaluation of nonacidic 10 with the characteristic N -acylated piperidine group obtained from SAR studies...
February 8, 2018: ACS Medicinal Chemistry Letters
Wojciech Majeran, Jean-Pierre Le Caer, Lalit Ponnala, Thierry Meinnel, Carmela Giglione
N-terminal myristoylation (MYR) is a biologically important co-translational protein lipidation. MYR is difficult to detect in vivo and challenging to predict in silico. We developed a targeted proteomics strategy to identify the Arabidopsis thaliana myristoylated (MYRed) proteome in specific sub-cellular compartments. This global profiling approach allowed us to: (i) identify one third of all open reading frames of the A. thaliana proteome including 54% of the predicted myristoylome; and (ii) establish the first comprehensive plant myristoylome, featuring direct evidence of MYR in 72 proteins...
February 16, 2018: Plant Cell
Roman Szostak, Michal Szostak
Resonance energies and proton affinities of N-acyl-glutarimides, compared with related twisted acyclic amides of relevance to N-C(O) cross-coupling, are reported. The data demonstrate that amidic resonance in N-acyl-glutarimides practically disappears (E R < 2.8 kcal/mol), while, intriguingly, these amides favor O-protonation despite significant twist. In some cases, N-acyl-glutarimides undergo intramolecular N- to O-acyl migration, indicative of high capacity as acylating reagents. The understanding provided for the high reactivity of N-acyl-glutarimides should facilitate the development of a broadly general N-C(O) amide activation platform...
February 16, 2018: Organic Letters
Zahir Hussain, Toru Uyama, Katsuhisa Kawai, Smriti Sultana Binte Mustafiz, Kazuhito Tsuboi, Nobukazu Araki, Natsuo Ueda
N-Acyl-phosphatidylethanolamine (NAPE) is known to be a precursor for various bioactive N-acylethanolamines including the endocannabinoid anandamide. NAPE is produced in mammals through the transfer of an acyl chain from certain glycerophospholipids to phosphatidylethanolamine (PE) by Ca 2+ -dependent or -independent N-acyltransferases. The Ɛ isoform of mouse cytosolic phospholipase A 2 (cPLA 2 Ɛ) was recently identified as a Ca 2+ -dependent N-acyltransferase (Ca-NAT). In the present study, we first showed that two isoforms of human cPLA 2 Ɛ function as Ca-NAT...
February 12, 2018: Biochimica et Biophysica Acta
Zhangjian Hu, Shujun Shao, Chenfei Zheng, Zenghui Sun, Junying Shi, Jingquan Yu, Zhenyu Qi, Kai Shi
N-decanoyl-homoserine lactone activates plant systemic resistance against Botrytis cinerea in tomato plants, which is largely dependent on jasmonic acid biosynthesis and signal transduction pathways. Rhizosphere bacteria secrete N-acylated-homoserine lactones (AHLs), a type of specialized quorum-sensing signal molecule, to coordinate their population density during communication with their eukaryotic hosts. AHLs behave as low molecular weight ligands that are sensed by plants and promote the host's resistance against foliar pathogens...
February 14, 2018: Planta
Christina L Wysoczynski-Horita, Michelle E Boursier, Ryan Hill, Kirk Hansen, Helen E Blackwell, Mair E A Churchill
Pseudomonas aeruginosa is an opportunistic pathogen that uses the process of quorum sensing (QS) to coordinate the expression of many virulence genes. During quorum sensing, N-acyl-homoserine lactone (AHL) signaling molecules regulate the activity of three LuxR-type transcription factors, LasR, RhlR, and QscR. To better understand P. aeruginosa QS signal reception, we examined the mechanism underlying the response of QscR to synthetic agonists and antagonists using biophysical and structural approaches. The structure of QscR bound to a synthetic agonist reveals a novel mode of ligand binding supporting a general mechanism for agonist activity...
February 13, 2018: Molecular Microbiology
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