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Klaas J van Wijk, Felix Kessler
Plastoglobuli (PGs) are plastid lipoprotein particles surrounded by a membrane lipid monolayer. PGs contain small specialized proteomes and metabolomes. They are present in different plastid types (e.g., chloroplasts, chromoplasts, and elaioplasts) and are dynamic in size and shape in response to abiotic stress or developmental transitions. PGs in chromoplasts are highly enriched in carotenoid esters and enzymes involved in carotenoid metabolism. PGs in chloroplasts are associated with thylakoids and contain ∼30 core proteins (including six ABC1 kinases) as well as additional proteins recruited under specific conditions...
January 25, 2017: Annual Review of Plant Biology
Catherine Biniek, Eiri Heyno, Jerzy Kruk, Francesca Sparla, Paolo Trost, Anja Krieger-Liszkay
The quinone reductase NQR and the b-type cytochrome AIR12 of the plasma membrane are important for the control of reactive oxygen species in the apoplast. AIR12 and NQR are two proteins attached to the plant plasma membrane which may be important for generating and controlling levels of reactive oxygen species in the apoplast. AIR12 (Auxin Induced in Root culture) is a single gene of Arabidopsis that codes for a mono-heme cytochrome b. The NADPH quinone oxidoreductase NQR is a two-electron-transferring flavoenzyme that contributes to the generation of O 2(•-) in isolated plasma membranes...
April 2017: Planta
Lei Wang, Qingwei Li, Aihong Zhang, Wen Zhou, Rui Jiang, Zhipan Yang, Huixia Yang, Xiaochun Qin, Shunhua Ding, Qingtao Lu, Xiaogang Wen, Congming Lu
Phytyl-diphosphate, which provides phytyl moieties as a common substrate in both tocopherol and phylloquinone biosynthesis, derives from de novo isoprenoid biosynthesis or a salvage pathway via phytol phosphorylation. However, very little is known about the role and origin of the phytyl moiety for phylloquinone biosynthesis. Since VTE6, a phytyl-phosphate kinase, is a key enzyme for phytol phosphorylation, we characterized Arabidopsis vte6 mutants to gain insight into the roles of phytyl moieties in phylloquinone biosynthesis and of phylloquinone in photosystem I (PSI) biogenesis...
January 9, 2017: Molecular Plant
Virginia Pérez Fernández, Salvatore Ventura, Pierpaolo Tomai, Roberta Curini, Alessandra Gentili
This paper describes an analytical approach, based on LC-diode array detector-MS/MS (LC-DAD-MS/MS), for characterizing the fat-soluble micronutrient fraction in rainbow trout (Oncorhynchus mykiss). Two different procedures were applied to isolate the analytes from liver and muscle tissue: overnight cold saponification to hydrolyze bound forms and to simplify the analysis; matrix solid-phase dispersion to avoid artifacts and to maintain unaltered the naturally occurring forms. Analytes were separated on a C30 analytical column by using a nonaqueous reversed mobile phase compatible with the atmospheric pressure chemical ionization...
March 2017: Electrophoresis
Kristin M McCabe, Sarah L Booth, Xueyan Fu, Emilie Ward, Michael A Adams, Rachel M Holden
BACKGROUND: Patients with chronic kidney disease (CKD) have very high levels of uncarboxylated, inactive, extra-hepatic vitamin K-dependent proteins measured in circulation, putting them at risk for complications of vitamin K deficiency. The major form of vitamin K found in the liver is phylloquinone (K1). Menaquinone-4 (MK-4) is the form of vitamin K that is preferentially found in extra-hepatic tissues. METHODS: In the present study, we assessed tissue concentrations of K1 and MK-4 and the expression of vitamin K-related genes in a rat model of adenine-induced CKD...
2017: American Journal of Nephrology
Sanjeev Kumar, Suchandra Chatterjee, Jyoti Tripathi, Satyendra Gautam
During in vitro analysis, spinach (Spinacea oleracea L.) leaf extracts displayed varying antimutagenicity when analyzed in models including human lymphoblast (TK(+/-)) cell line (thymidine kinase gene mutation assay) and Escherichia coli MG1655 (rifampicin resistance assay) against chemically (ethyl methanesulfonate and 5-azacytidine) induced mutagenicity. Highest antimutagenicity was displayed by the quinone extract. The principal bioactive compound exhibited fluorescence in TLC at 366 nm (termed C4) resolved at Rf 0...
November 23, 2016: Journal of Agricultural and Food Chemistry
Aoife Hayes, Áine Hennessy, Janette Walton, Breige A McNulty, Alice J Lucey, Máiréad Kiely, Albert Flynn, Kevin D Cashman
BACKGROUND: Data from a nationally representative sample of 18- to 64-y-old Irish adults conducted in 1999 highlighted low phylloquinone intakes. That survey, however, did not include older adults (aged ≥65 y), a subgroup that is potentially at higher risk of low phylloquinone intakes, or a biomarker of vitamin K status. OBJECTIVES: The objectives of this work were to measure the phylloquinone intake and its adequacy and the serum percentage of undercarboxylated osteocalcin (%ucOC), a vitamin K status biomarker, in a nationally representative sample of Irish adults aged 18-90 y, and to compare these newer data on dietary phylloquinone in adults aged 18-64 y with those from the previous survey...
October 12, 2016: Journal of Nutrition
Maria Fusaro, Maurizio Gallieni, Maria Antonietta Rizzo, Andrea Stucchi, Pierre Delanaye, Etienne Cavalier, Rosa M A Moysés, Vanda Jorgetti, Giorgio Iervasi, Sandro Giannini, Fabrizio Fabris, Andrea Aghi, Stefania Sella, Francesco Galli, Valentina Viola, Mario Plebani
Vitamin K (phylloquinone or vitamin K1 and menaquinones or vitamin K2) plays an important role as a cofactor in the synthesis of hepatic blood coagulation proteins, but recently has also aroused an increasing interest for its action in extra-hepatic tissues, in particular in the regulation of bone and vascular metabolism. The accurate measurement of vitamin K status in humans is still a critical issue. Along with indirect assays, such as the undercarboxylated fractions of vitamin K-dependent proteins [prothrombin, osteocalcin (OC), and matrix gla protein], the direct analysis of blood levels of phylloquinone and menaquinones forms might be considered a more informative and direct method for assessing vitamin K status...
October 12, 2016: Clinical Chemistry and Laboratory Medicine: CCLM
Hani M Khojah, Sameh Ahmed, Mahran S Abdel-Rahman, Khaled M Alkhalil, Al-Badr Hamza
The aim of this study was to evaluate the possible role of vitamin K homologs as potential biomarkers for disease activity in patients with rheumatoid arthritis (RA). In this study, 42 patients with RA and 40 healthy controls were enrolled. Serum levels of vitamin K homologs were measured using a high-performance liquid chromatography-fluorescence method. Different biochemical and clinical markers for disease activity were measured and correlated with serum levels of vitamin K homologs. There were no significant differences between RA patients and healthy subjects in demographic data...
October 8, 2016: Journal of Bone and Mineral Metabolism
Øivind Midttun, Adrian McCann, Ove Aarseth, Marit Krokeide, Gry Kvalheim, Klaus Meyer, Per Magne Ueland
Targeted metabolic profiling characterized by complementary platforms, multiplexing and low volume consumption are increasingly used for studies using biobank material. Using liquid-liquid extraction, we developed a sample workup suitable for quantification of 6 fat- and 26 water-soluble biomarkers. 50μL of serum/plasma was mixed with dithioerythritol, ethanol and isooctane/chloroform. The organic layer was used for analysis of the fat-soluble vitamins all-trans retinol (A), 25-hydroxyvitamin D2, 25-hydroxyvitamin D3, α-tocopherol (E), γ-tocopherol (E) and phylloquinone (K1) by LC-MS/MS...
October 7, 2016: Analytical Chemistry
Sabine R Zwakenberg, Nicole R den Braver, Anouk I P Engelen, Edith J M Feskens, Cees Vermeer, Jolanda M A Boer, W M Monique Verschuren, Yvonne T van der Schouw, Joline W J Beulens
BACKGROUND & AIMS: Vitamin K has been associated with various health outcomes, including non-fatal cardiovascular diseases (CVD) and cancer. However, little is known about the association between vitamin K intake and all-cause and cause specific mortality. This study aims to investigate the association between vitamin K intake and all-cause and cause-specific mortality. METHODS: This prospective cohort study included 33,289 participants from the EPIC-NL cohort, aged 20-70 years at baseline and recruited between 1993 and 1997...
August 30, 2016: Clinical Nutrition: Official Journal of the European Society of Parenteral and Enteral Nutrition
Rodrigo A C Sussmann, Marcilio M de Moraes, Gerardo Cebrián-Torrejón, Exequiel O Porta, Antonio Doménech-Carbó, Lydia F Yamaguchi, Alejandro M Katzin, Massuo J Kato
Phylloquinone is a redox active naphthoquinone involved in electron transport in plants. The function of this reduced form remains unclear due to its instability, which has precluded detection. Herein, a simple method that permits the stabilization of the reduced form of phylloquinone by di-O-methylation and HPLC detection is described.
October 15, 2016: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Kevin Benham, Robert Hodyss, Facundo M Fernández, Thomas M Orlando
We demonstrate the first application of laser-induced acoustic desorption (LIAD) and atmospheric pressure photoionization (APPI) as a mass spectrometric method for detecting low-polarity organics. This was accomplished using a Lyman-α (10.2 eV) photon generating microhollow cathode discharge (MHCD) microplasma photon source in conjunction with the addition of a gas-phase molecular dopant. This combination provided a soft desorption and a relatively soft ionization technique. Selected compounds analyzed include α-tocopherol, perylene, cholesterol, phenanthrene, phylloquinone, and squalene...
November 2016: Journal of the American Society for Mass Spectrometry
Barbara Emonds-Alt, Nadine Coosemans, Thomas Gerards, Claire Remacle, Pierre Cardol
Phylloquinone (PhQ), or vitamin K1 , is an essential electron carrier (A1 ) in photosystem I (PSI). In the green alga Chlamydomonas reinhardtii, which is a model organism for the study of photosynthesis, a detailed characterization of the pathway is missing with only one mutant deficient for MEND having been analyzed. We took advantage of the fact that a double reduction of plastoquinone occurs in anoxia in the A1 site in the mend mutant, interrupting photosynthetic electron transfer, to isolate four new phylloquinone-deficient mutants impaired in MENA, MENB, MENC (PHYLLO) and MENE...
January 2017: Plant Journal: for Cell and Molecular Biology
Linda E T Vissers, Geertje W Dalmeijer, Jolanda M A Boer, W M Monique Verschuren, Yvonne T van der Schouw, Joline W J Beulens
BACKGROUND AND AIMS: A high dietary intake of vitamin K1 (phylloquinone) and vitamin K2 (menaquinones) is thought to decrease cardiovascular disease risk by reducing vascular calcification. The objective of this study is to explore if there is a relationship between phylloquinone and menaquinones intake and risk of PAD. METHODS: We investigated the association between intake of phylloquinone and menaquinones with PAD in a prospective cohort with 36,629 participants...
September 2016: Atherosclerosis
Julia Khéde Dourado Villa, Marisa Alves Nogueira Diaz, Virgínia Ramos Pizziolo, Hércia Stampini Duarte Martino
Osteoporosis is a public health concern associated with an increased risk of bone fractures and vascular calcification. Vitamin K presents unique benefits on these issues, although understudied. The two main forms of vitamin K are phylloquinone (vitamin K1) and menaquinone (vitamin K2). In this study, it was especially investigated the action of vitamin K2 in bones and vessels. Vitamin K2 has shown to stimulate bone formation by promoting osteoblast differentiation and carboxylation of osteocalcin, and increasing alkaline phosphatase, insulin-like growth factor-1, growth differentiation factor-15, and stanniocalcin 2 levels...
July 20, 2016: Critical Reviews in Food Science and Nutrition
Stephanie G Harshman, Xueyan Fu, J Philip Karl, Kathryn Barger, Stefania Lamon-Fava, Athan Kuliopulos, Andrew S Greenberg, Donald Smith, Xiaohua Shen, Sarah L Booth
BACKGROUND: There has been limited characterization of biological variables that impact vitamin K metabolism. This gap in knowledge can limit the translation of data obtained from preclinical animal studies to future human studies. OBJECTIVE: The purpose of this study was to determine the effects of diet, sex, and housing on serum, tissue, and fecal vitamin K concentrations and gene expression in C57BL6 mice during dietary vitamin K manipulation. METHODS: C57BL6 4-mo-old male and female mice were randomly assigned to conventional or suspended-wire cages and fed control [1400 ± 80 μg phylloquinone (PK)/kg] or deficient (31 ± 0...
August 2016: Journal of Nutrition
Takayuki Tohge, Alisdair R Fernie
There has been a massive increase in the number of reports about the medicinal benefits of the consumption of phenylpropanoids derived from the plastidic shikimate pathway. These benefits include anti-retroviral, anti-hypertensive, anti-inflammatory, anti-aging and insulin-sensitizing activities, the reduction of the risk of a range of chronic diseases including cardiovascular disease, cancer and osteoporosis as well as inhibition of LDL (low-density lipoprotein) oxidation. In addition, chorismate-derived salicylate which was originally isolated from plants, albeit now under chemical production, is massively used for pain relief in the form of acetylsalycilic acid, namely aspirin...
June 24, 2016: Mini Reviews in Medicinal Chemistry
Gilles J Basset, Scott Latimer, Abdelhak Fatihi, Eric Soubeyrand, Anna Block
Phylloquinone is a prenylated naphthoquinone that is synthesized exclusively by plants, green algae, and some species of cyanobacteria, where it serves as a vital electron carrier in photosystem I and as an electron acceptor for the formation of protein disulfide bonds. In humans and other vertebrates, phylloquinone plays the role of a vitamin (vitamin K1) that is required for blood coagulation and bone and vascular metabolism. Phylloquinone from green leafy vegetables and vegetable oil represents the major dietary source of vitamin K for humans...
June 22, 2016: Mini Reviews in Medicinal Chemistry
Yumiao Zhang, Wentao Song, Jumin Geng, Upendra Chitgupi, Hande Unsal, Jasmin Federizon, Javid Rzayev, Dinesh K Sukumaran, Paschalis Alexandridis, Jonathan F Lovell
Injectable hydrophobic drugs are typically dissolved in surfactants and non-aqueous solvents which can induce negative side-effects. Alternatives like 'top-down' fine milling of excipient-free injectable drug suspensions are not yet clinically viable and 'bottom-up' self-assembled delivery systems usually substitute one solubilizing excipient for another, bringing new issues to consider. Here, we show that Pluronic (Poloxamer) block copolymers are amenable to low-temperature processing to strip away all free and loosely bound surfactant, leaving behind concentrated, kinetically frozen drug micelles containing minimal solubilizing excipient...
2016: Nature Communications
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