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Gene cloning of an efficiency oleate hydratase from Stenotrophomonas nitritireducens for polyunsaturated fatty acids and its application in the conversion of plant oils to 10‐hydroxy fatty acids
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Woo‐Ri Kang Min‐Ju Seo Kyung‐Chul Shin Jin‐Byung Park Deok‐Kun Oh 《Biotechnology and bioengineering》2017,114(1):74-82
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Production of 8,11‐dihydroxy and 8‐hydroxy unsaturated fatty acids from unsaturated fatty acids by recombinant Escherichia coli expressing 8,11‐linoleate diol synthase from Penicillium chrysogenum
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Hydroxy unsaturated fatty acids can be used as antimicrobial surfactants. 8,11‐Linoleate diol synthase (8,11‐LDS) catalyzes the conversion of unsaturated fatty acid to 8‐hydroperoxy unsaturated fatty acid, and it is subsequently isomerized to 8,11‐dihydroxy unsaturated fatty acid by the enzyme. The optimal reaction conditions of recombinant Escherichia coli expressing Penicillium chrysogenum 8,11‐LDS for the production of 8,11‐dihydroxy‐9,12(Z,Z)‐octadecadienoic acid (8,11‐DiHODE), 8,11‐dihydroxy‐9,12,15(Z,Z,Z)‐octadecatrienoic acid (8,11‐DiHOTrE), 8‐hydroxy‐9(Z)‐hexadecenoic acid (8‐HHME), and 8‐hydroxy‐9(Z)‐octadecenoic acid (8‐HOME) were pH 7.0, 25°C, 10 g/L linoleic acid, and 20 g/L cells; pH 6.0, 25°C, 6 g/L α‐linolenic acid, and 60 g/L cells; pH 7.0, 25°C, 8 g/L palmitoleic acid, and 25 g/L cells; and pH 8.5, 30°C, 6 g/L oleic acid, and 25 g/L cells, respectively. Under these optimized conditions, the recombinant cells produced 6.0 g/L 8,11‐DiHODE for 60 min, with a conversion of 60% (w/w) and a productivity of 6.0 g/L/h; 4.3 g/L 8,11‐DiHOTrE for 60 min, with a conversion of 72% (w/w) and a productivity of 4.3 g/L/h; 4.3 g/L 8‐HHME acid for 60 min, with a conversion of 54% (w/w) and a productivity of 4.3 g/L/h; and 0.9 g/L 8‐HOME for 30 min, with a conversion of 15% (w/w) and a productivity of 1.8 g/L/h. To best of our knowledge, this is the first report on the biotechnological production of 8,11‐DiHODE, 8,11‐DiHOTrE, 8‐HHME, and 8‐HOME. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:390–396, 2017 相似文献
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Ultraviolet‐B (UVB) radiation due sunlight can result in sunburns and/or suntans. Sunburn occurs only several hours after solar UVB radiation, while a suntan requires several days to several weeks to develop. In the present study, we measured serum and urine levels of melanin‐related metabolites, 5‐S‐cysteinyldopa (5‐S‐CD) and 6‐hydroxy‐5‐methoxyindole‐2‐carboxylic acid (6H5MI2C), in nine subjects exposed to normal sunlight over the course of 12 months. We collected samples in the middle of each month and examined the variation of the markers, the correlation between them, and their correlation with solar UVB radiation. Those markers exhibited a seasonal variation with lower values in the winter and higher values in the summer. Levels of 5‐S‐CD and 6H5MI2C in the serum showed 48% and 54% increases in the summer compared with those in the winter, respectively. Comparison of 5‐S‐CD in the serum and urine showed the highest correlation (r2 = 0.344), followed by the pair of 5‐S‐CD and 6H5MI2C in the serum. Levels of 5‐S‐CD in the serum showed the highest correlation (r2 = 0.729) with the mean solar UVB radiation during the first 10 d of the month, while 6H5MI2C in the serum was highly correlated (r2 = 0.483) with solar UVB radiation during the previous month. Levels of 5‐S‐CD and 6H5MI2C in the serum appear to reflect the degrees of skin injury and pigmentation in the skin, respectively. 相似文献
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5‐Fluorouridine ( 1 ) – a nucleoside antimetabolite with strong cancerostatic properties – was protected i) at the 2′‐ and 3′‐OH groups with a heptan‐4‐ylidene residue and ii) at the 5′‐OH group with a (4‐methoxyphenyl)(diphenyl)methyl residue. This fully protected compound, 3 , was submitted to a Mitsunobu reaction with the N‐hydroxysuccinimide (NHS) ester, 5 , of (2E)‐10‐hydroxydec‐2‐enoic acid ( 4 ) which gave nucleolipid 6 . The latter was detritylated with Cl2CHCOOH to yield the co‐drug 7 as NHS ester. 相似文献
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Salma M. Z. Al‐Kindy Zahra Al‐Mafrigi Musa S. Shongwe Fakhr Eldin O. Suliman 《Luminescence》2011,26(6):462-470
A sensitive and selective spectrofluorimetric method has been developed for the rapid determination of aluminium. This method is based on the complex formation between aluminium and 2‐hydroxy‐1‐naphthylidene‐(8‐aminoquinoline) (HNAQ). The optimum conditions for the complex formation were a metal‐to‐ligand (M : L) stoichiometric ratio of 1:1, a pH of 5.5 and a 0.20 m acetate buffer. The fluorescence of the complex was monitored at an emission wavelength of 502 nm with excitation at 438 nm. Under these conditions, linear calibration curves were obtained in the ranges 0.05–1 and 1–5 ppm. The detection limit was 3.4 ppb for the former and 13.5 ppb for the latter. The maximum relative standard deviation of the method for an aluminium standard of 200 ppb was 1.5% (n = 5). This method was successfully applied for the determination of aluminium in drinking water, pharmaceutical antacid tablets and suspension samples. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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In comparative fluorescence gel electrophoresis experiments, cross‐talk was detected. It was traced back to a failure in the quenching process in typical labelling protocols. Despite a huge excess of potential reaction sites for the N‐hydroxy‐succinimide–ester‐coupled dye, sufficient active dye molecules were available after the quenching step to label protein molecules un‐specifically. It could be shown that only a 100‐fold increase in the amount of quencher will silence residual dye to such an extent that no artificial signals are detected. 相似文献
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Jia Tang Yingchao Liu Dawei Qi Guoping Yao Chunhui Deng Xiangmin Zhang 《Proteomics》2009,9(22):5046-5055
In this study, an on‐plate‐selective enrichment method is developed for fast and efficient glycopeptide investigation. Gold nanoparticles were first spotted and sintered on a stainless‐steel plate, then modified with 4‐mercaptophenylboronic acid to provide porous substrate with large specific surface and dual functions. These spots were used to selectively capture glycopeptides from peptide mixtures and the captured target peptides could be analyzed by MALDI‐MS simply by deposition of 2,5‐dihydroxybenzoic acid matrix. Horseradish peroxidase was employed as a standard glycoprotein to investigate the enrichment efficiency. In this way, the enrichment, washing and detection steps can all be fulfilled on a single MALDI target plate. The relatively small sample amount needed, low detection limit and rapid selective enrichment have made this on‐plate strategy promising for online enrichment of glycopeptides, which could be applied in high‐throughput proteome research. 相似文献
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Hidehisa Kawashima Nobuko Watanabe Hisako K. Ijuin Masakatsu Matsumoto 《Luminescence》2013,28(5):696-704
Bicyclic dioxetanes 2a–c bearing a 2′‐alkoxy‐2‐hydroxy‐1,1′‐binaphthyl‐7‐yl moiety were effectively synthesized and their base‐induced chemiluminescent decomposition was investigated by the use of alkaline metal (Na+ and K+) or Mg2+ alkoxide in MeOH. When 2a–c were treated with tetrabutylammonium fluoride (TBAF) in dimethyl sulfoxide (DMSO) as a reference system, they showed chemiluminescence as a flash of orange light (maximum wavelength λmaxCL = 573–577 nm) with efficiency ΦCL = 6–8 × 10–2. On the other hand, for an alkaline metal (Na+ or K+) alkoxide/MeOH system, 2a–c decomposed slowly to emit a glow of chemiluminescence, the spectra of which were shifted slightly toward red from the TBAF/DMSO system, and ΦCL (= 1.4–2.3 × 10–3) was considerably decreased. In addition, Mg(OMe)2 was found to play a characteristic role as a base for the chemiluminescent decomposition of 2a–c through coordination to the intermediary oxidoaryl‐substituted dioxetanes 13. Thus, Mg2+ increased ΦCL to more than twice those with Na+ or K+, while it shifted λmaxCL considerably toward blue (λmaxCL = 550–566 nm). Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Yihui Chen Ana G. Petrovic Marin Roje Gennaro Pescitelli Margaret M. Kayser Yan Yang Nina Berova Gloria Proni 《Chirality》2010,22(1):140-152
This article describes an application of the host‐guest chiral recognition approach called tweezer methodology for the determination of the absolute configuration of 3‐hydroxy‐β‐lactams. These substrates represent challenging cases due to their chemical reactivity, the presence of multiple stereogenic centers and several functional groups which offer various possibilities of binding to the Zn‐porphyrin host. OPLS‐2005, the force field used in this work to predict the interporphyrin twist, modeled correctly the host‐guest complexation mechanism and revealed conformational details of the bound substrates. The computational study also suggested that in cases where an increase in the magnitude of the stereodifferentiation and an intense experimental CD are observed, the bound conformation of the conjugates are hydrogen bonded. The present investigation provides evidence that when the tweezer method is assisted by the OPLS‐2005 based computational approach, it can be successfully applied to the configurational and conformational elucidation of multi‐functional compounds with multiple stereogenic centers. Chirality, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
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Improved fruit α‐tocopherol,carotenoid, squalene and phytosterol contents through manipulation of Brassica juncea 3‐HYDROXY‐3‐METHYLGLUTARYL‐COA SYNTHASE1 in transgenic tomato
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Pan Liao Xinjian Chen Mingfu Wang Thomas J. Bach Mee‐Len Chye 《Plant biotechnology journal》2018,16(3):784-796
3‐Hydroxy‐3‐methylglutaryl‐coenzyme A synthase (HMGS) in the mevalonate (MVA) pathway generates isoprenoids including phytosterols. Dietary phytosterols are important because they can lower blood cholesterol levels. Previously, the overexpression of Brassica juncea wild‐type (wt) and mutant (S359A) BjHMGS1 in Arabidopsis up‐regulated several genes in sterol biosynthesis and increased sterol content. Recombinant S359A had earlier displayed a 10‐fold higher in vitro enzyme activity. Furthermore, tobacco HMGS overexpressors (OEs) exhibited improved sterol content, plant growth and seed yield. Increased growth and seed yield in tobacco OE‐S359A over OE‐wtBjHMGS1 coincided with elevations in NtSQS expression and sterol content. Herein, the overexpression of wt and mutant (S359A) BjHMGS1 in a crop plant, tomato (Solanum lycopersicum), caused an accumulation of MVA‐derived squalene and phytosterols, as well as methylerythritol phosphate (MEP)‐derived α‐tocopherol (vitamin E) and carotenoids, which are important to human health as antioxidants. In tomato HMGS‐OE seedlings, genes associated with the biosyntheses of C10, C15 and C20 universal precursors of isoprenoids, phytosterols, brassinosteroids, dolichols, methylerythritol phosphate, carotenoid and vitamin E were up‐regulated. In OE‐S359A tomato fruits, increased squalene and phytosterol contents over OE‐wtBjHMGS1 were attributed to heightened SlHMGR2, SlFPS1, SlSQS and SlCYP710A11 expression. In both tomato OE‐wtBjHMGS1 and OE‐S359A fruits, the up‐regulation of SlGPS and SlGGPPS1 in the MEP pathway that led to α‐tocopherol and carotenoid accumulation indicated cross‐talk between the MVA and MEP pathways. Taken together, the manipulation of BjHMGS1 represents a promising strategy to simultaneously elevate health‐promoting squalene, phytosterols, α‐tocopherol and carotenoids in tomato, an edible fruit. 相似文献
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Parathyroid hormone‐induced down‐regulation of miR‐532‐5p for matrix metalloproteinase‐13 expression in rat osteoblasts
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Vishal Mohanakrishnan Arumugam Balasubramanian Gokulnath Mahalingam Nicola Chennell Partridge Ilangovan Ramachandran Nagarajan Selvamurugan 《Journal of cellular biochemistry》2018,119(7):6181-6193
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Yuhong Zhou Lin Deng Dandan Zhao Lanlan Chen Zhen Yao Xiaowei Guo Xue Liu Lifang Lv Bing Leng Wei Xu Guofen Qiao Hongli Shan 《Journal of cellular and molecular medicine》2016,20(3):495-505
Cardiac fibrosis is a major cause of heart failure. MicroRNAs (miRs) are important epigenetic regulators of cardiac function and cardiovascular diseases, including cardiac fibrosis. This study aimed to explore the role of miR‐503 and its mechanisms in regulating cardiac fibrosis. miR‐503 was found up‐regulated in the mouse LV tissues subjected to transverse aortic constriction (TAC) and in neonatal cardiac fibroblasts (CFs) cultured with Angiotension II. The role of miR‐503 in regulating CF cell proliferation and/or collagen production in mice neonatal CFs were determined using an MTT assay and RT‐PCR respectively. Forced expression of miR‐503 increased the cellular proliferation and collagen production in mice neonatal CFs. The effects were abrogated by cotransfection with AMO‐503 (a specific inhibitor of miR‐503). Injection of antagomiR‐503 elevated cardiac function and inhibited the expression of connective tissue growth factor (CTGF) and transforming growth factor (TGF)‐β in the TAC mice. Additional analysis revealed that Apelin‐13 is a direct target of miR‐503, as the overexpression of miR‐503 decreased the protein and mRNA expression levels of Apelin‐13. In the CFs with pre‐treatment of AngII, we transfected AMO‐503 into the cells treated with siRNA‐APLN. siRNA‐APLN abolished the effects of AMO‐503 on the production of collagen I and III and the expression of TGF‐β and CTGF. Furthermore, pre‐treatment of CFs with Apelin‐13 (1–100 nmol/l) inhibited angiotensin II‐mediated collagen production and activation of CTGF and TGF‐β. So we conclude that miR‐503 promotes cardiac fibrosis via miR‐503‐Apelin‐13‐TGF‐β‐CTGF‐collagen production pathway. Thus, miR‐503 is a promising therapeutic target for reducing cardiac fibrosis. 相似文献
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Facile synthesis of magnetic poly(styrene‐co‐4‐vinylbenzene‐boronic acid) microspheres for selective enrichment of glycopeptides
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In this work, the composites of magnetic Fe3O4@SiO2@poly (styrene‐co‐4‐vinylbenzene‐boronic acid) microspheres with well‐defined core–shell–shell structure were facilely synthesized and applied to selectively enrich glycopeptides. Due to the relatively large amount of vinyl groups introduced by 3‐methacryloxy‐propyl‐trimethoxysilane on the core‐shell surface, the poly(styrene‐co‐4‐vinylbenzeneboronic acid) (PSV) was coated with high efficiency, resulting in a large amount of boronic acid on the outermost polymer shell of the Fe3O4@SiO2@PSV microspheres, which is of great importance to improve the enrichment efficiency for glycopeptides. The obtained Fe3O4@SiO2@PSV microspheres were successfully applied to the enrichment of glycopeptides with strong specificity and high selectivity, evaluated by capturing glycopeptides from tryptic digestion of model glycoprotein HRP diluted to 0.05 ng/μL (1.25 × 10?13 mol, 100 μL), tryptic digest of HRP and nonglycosylated BSA up to the ratio of 1:120 w/w and the real complex sample human serum with 103 unique N‐glycosylation peptides of 46 different glycoproteins enriched. 相似文献
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Reduced blood‐brain barrier expression of fatty acid‐binding protein 5 is associated with increased vulnerability of APP/PS1 mice to cognitive deficits from low omega‐3 fatty acid diets
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Yijun Pan Kwok H. C. Choy Philip J. Marriott Siew Y. Chai Martin J. Scanlon Christopher J. H. Porter Jennifer L. Short Joseph A. Nicolazzo 《Journal of neurochemistry》2018,144(1):81-92
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Ui Joung Youn Jun‐Ho Lee Yoo Jin Lee Joo Won Nam Hyunsu Bae Eun‐Kyoung Seo 《化学与生物多样性》2010,7(9):2296-2302
Four known alkyl 4‐hydroxybenzoates, i.e., methyl 4‐hydroxybenzoate ( 1 ), ethyl 4‐hydroxybenzoate ( 2 ), propyl 4‐hydroxybenzoate ( 3 ), and butyl 4‐hydroxybenzoate ( 4 ), were isolated from the seeds of Nelumbo nucifera Gaertner (Nymphaeaceae) for the first time. The structures of the isolates were identified by 1D‐ and 2D‐NMR spectroscopy and comparison with published values. The compounds were evaluated for their effects on the 5‐HT‐stimulated inward current (I5‐HT) mediated by the human 5‐HT3A receptors expressed in Xenopus oocytes. Compounds 1 and 2 enhanced the I5‐HT, but 4 reduced it. These results indicate that 4 is an inhibitor of the 5‐HT3A receptors expressed in Xenopus oocytes. 相似文献