Read by QxMD icon Read

Branched-chain amino acid

Tathyana Mar Amorim Franco, Subray S Hegde, John S Blanchard
The biosynthetic pathway of the branched-chain amino acids is essential for M. tuberculosis growth and survival. We report here the kinetic and chemical mechanism of the pyridoxal 5'-phosphate (PLP)-dependent branched-chain aminotransferase, IlvE, from M. tuberculosis (MtIlvE). This enzyme is responsible for the final step of the synthesis of the branched-chain amino acids isoleucine, leucine and valine. As seen in other aminotransferases, MtIlvE displays a ping-pong kinetic mechanism. pK values were identified from the pH dependence on V as well as V/K, indicating that the phosphate ester of the PLP cofactor, as well as the α-amino group from L-glutamate and the active site Lys204, play roles in acid-base catalysis and binding, respectively...
October 25, 2016: Biochemistry
Jari E Kaikkonen, Peter Würtz, Emmi Suomela, Miia Lehtovirta, Antti J Kangas, Antti Jula, Vera Mikkilä, Jorma S A Viikari, Markus Juonala, Tapani Rönnemaa, Nina Hutri-Kähönen, Mika Kähönen, Terho Lehtimäki, Pasi Soininen, Mika Ala-Korpela, Olli T Raitakari
: Non-alcoholic fatty liver is associated with obesity-related metabolic disturbances, but little is known about the metabolic perturbations preceding fatty liver disease. We performed comprehensive metabolic profiling to assess how circulating metabolites, such as lipoprotein lipids, fatty acids, amino acids and glycolysis-related metabolites, reflect the presence of and future risk for fatty liver in young adults. Sixty-eight lipids and metabolites were quantified by nuclear magnetic resonance metabolomics in the population-based Young Finns Study from serum collected in 2001 (n=1,575), 2007 (n=1,509) and 2011 (n=2,002)...
October 24, 2016: Hepatology: Official Journal of the American Association for the Study of Liver Diseases
Bo Zhang, Gui-Zhi Sun, Min-Ling Zhu, Yue Li, Dian-Jun Sun, Bo Zhang, Xiu-Ping Bai
OBJECTIVES: CST has been recently identified as a mediator of various beneficial effects in animal models of sepsis. At present, no data are available concerning the levels of CST in sepsis patients. In sepsis the plasma amino acid pattern is characterized by decreased branced chain amino acids (BCAAs). We investigated the levels of plasma CST or branched-chain α-ketoacid dehydrogenase kinase (BCKDK) and their relationship to component traits in patients with sepsis. DESIGN AND METHODS: We studied 228 patients and divided them into two groups based on severity of infection...
October 20, 2016: Peptides
Raj Kumar Sharma, Kumudesh Mishra, Alvina Farooqui, Anu Behari, Vinay Kumar Kapoor, Neeraj Sinha
OBJECTIVE AND DESIGN: We present in this article (1)H nuclear magnetic resonance (NMR)-based metabolic approach to screen the serum metabolic alterations in human gallbladder inflammation with chronic cholecystitis (CC). MATERIAL/METHODS: Total of 71 human serum samples was divided into two groups, (n = 41, CC) and (n = 30 control). (1)H NMR metabolic profiling was carried out for investigation of metabolic alterations. Multivariate statistical analysis was applied for pattern recognition and identification of metabolites playing crucial role in gallbladder inflammation...
October 21, 2016: Inflammation Research: Official Journal of the European Histamine Research Society ... [et Al.]
Mariya Markova, Olga Pivovarova, Silke Hornemann, Stephanie Sucher, Turid Frahnow, Katrin Wegner, Jürgen Machann, Klaus Jürgen Petzke, Johannes Hierholzer, Ralf Lichtinghagen, Christian Herder, Maren Carstensen-Kirberg, Michael Roden, Natalia Rudovich, Susanne Klaus, Ralph Thomann, Rosemarie Schneeweiss, Sascha Rohn, Andreas F H Pfeiffer
BACKGROUND & AIMS: Non-alcoholic fatty liver disease (NAFLD) is associated with increased risk of hepatic, cardiovascular, and metabolic diseases. High-protein diets, rich in methionine and branched chain amino acids (BCAAs), apparently reduce liver fat but may induce insulin resistance. We investigated the effects of diets high in animal protein vs plant protein, which differ in levels of methionine and BCAA, in subjects with type 2 diabetes and NAFLD. We examined levels of liver fat, lipogenic indices, markers of inflammation, serum levels of fibroblast growth factor 21 (FGF21), and activation of signaling pathways in adipose tissue...
October 17, 2016: Gastroenterology
Mary Anne D Chiong, Marilyn A Tan, Cynthia P Cordero, Esphie Grace D Fodra, Judy S Manliguis, Cristine P Lopez, Leslie Michelle M Dalmacio
BACKGROUND: Maple syrup urine disease (MSUD) is the most common inborn error of metabolism in the country. The cause of the neuropathology is still not well established although accumulation of branched chain amino acids (BCAA) and alteration in large neutral amino acids (LNAA) as well as energy deprivation are suggested. It is therefore the aim of this study to determine the plasma amino acid and urine organic acid profiles of patients with MSUD and correlate the findings with their neurologic features...
December 2016: Molecular Genetics and Metabolism Reports
Antonino Baez, Joseph Shiloach
The damaging effect of high oxygen concentration on growth of Escherichia coli is well established. Over-oxygenation increases the intracellular concentration of reactive oxygen species (ROS), causing the destruction of the [4Fe-4S] cluster of dehydratases and limiting the biosynthesis of both branched-chain amino acids and nicotinamide adenine dinucleotide. A key enzyme that reduces the damaging effect of superoxide is superoxide dismutase (SOD). Its transcriptional regulation is controlled by global transcription regulators that respond to changes in oxygen and iron concentrations and pH...
October 18, 2016: Antonie Van Leeuwenhoek
W Wu, J Xie, H Zhang
Dietary fibers (DFs), widely used as food additives to replace fat, can benefit metabolic disorders. Soluble and highly fermentable inulin (INU) and insoluble and less fermentable microcrystalline cellulose (MCC) have hypolipidemic or cholesterol-lowering effects, respectively. The current study was aimed at identifying plasma metabolite signatures and metabolic pathways associated with inclusion of DFs with different physiochemical properties, which will lead to a better understanding of functional pathways for DFs to improve metabolic health...
October 18, 2016: Food & Function
Ji-Young Choi, Ye Jin Kim, Ri Ryu, Su-Jung Cho, Eun-Young Kwon, Myung-Sook Choi
Green tea (GT) has various health effects, including anti-obesity properties. However, the multiple molecular mechanisms of the effects have not been fully determined. The aim of this study was to elucidate the anti-obesity effects of GT via the analysis of its metabolic and transcriptional responses based on RNA-seq profiles. C57BL/6J mice were fed a normal, high-fat (60% energy as fat), or high-fat + 0.25% (w/w) GT diet for 12 weeks. The GT extract ameliorated obesity, hepatic steatosis, dyslipidemia, and insulin resistance in diet-induced obesity (DIO) mice...
October 14, 2016: Nutrients
Ren-Yu Qu, Jing-Fang Yang, Yu-Chao Liu, Qiong Chen, Ge-Fei Hao, Cong-Wei Niu, Zhen Xi, Guang-Fu Yang
BACKGOUND: Acetohydroxyacid synthase (AHAS; EC is the first common enzyme in the biosynthetic pathway leading to the branched-chain amino acids in plants and a wide range of microorganisms. With the long-term and wide application of AHAS inhibitors, weed resistance is becoming a global problem, which leads to an urgent demand for novel inhibitors to antagonize both wild-type and resistant AHAS. RESULTS: Pyrimidinyl-Salicylic acid derivatives, as one of the main classes of commercial AHAS herbicides, show potential anti-resistant bioactivity to wild-type and P197L mutant...
October 17, 2016: Pest Management Science
Michael Vogt, Christian Brüsseler, Jan van Ooyen, Michael Bott, Jan Marienhagen
The pentanol isomers 2-methyl-1-butanol and 3-methyl-1-butanol represent commercially interesting alcohols due to their potential application as biofuels. For a sustainable microbial production of these compounds, Corynebacterium glutamicum was engineered for producing 2-methyl-1-butanol and 3-methyl-1-butanol via the Ehrlich pathway from 2-keto-3-methylvalerate and 2-ketoisocaproate, respectively. In addition to an already available 2-ketoisocaproate producer, a 2-keto-3-methylvalerate accumulating C. glutamicum strain was also constructed...
October 13, 2016: Metabolic Engineering
Daria Chrobok, Simon R Law, Bastiaan Brouwer, Pernilla Lindén, Agnieszka Ziolkowska, Daniela Liebsch, Reena Narsai, Bozena Szal, Thomas Moritz, Nicolas Rouhier, James Whelan, Per Gardestrom, Olivier Keech
The functions of mitochondria during leaf senescence, a type of programmed cell death aiming at the massive retrieval of nutrients from the senescing organ to the rest of the plant, remain elusive. Here, combining experimental and analytical approaches, we showed that mitochondrial integrity is conserved until the latest stages of leaf senescence, while their number drops by 30%. Adenylate phosphorylation state assays and mitochondrial respiratory measurements indicated that the leaf energy status is also maintained during this time period...
October 15, 2016: Plant Physiology
Lina Yao, Hui Shen, Nan Wang, Jaspaul Tatlay, Liang Li, Tin Wee Tan, Yuan Kun Lee
Microalgal neutral lipids (mainly in the form of triacylglycerols (TAGs)), feasible substrates for biofuel, are typically accumulated during the stationary growth phase. To make microalgal biofuels economically competitive with fossil fuels, generating strains that trigger TAG accumulation from the exponential growth phase is a promising biological approach. The regulatory mechanisms to trigger TAG accumulation from the exponential growth phase (TAEP) are important to be uncovered for advancing economic feasibility...
October 13, 2016: Plant Biotechnology Journal
Marion Rauter, Jakub Kasprzak, Karin Becker, Jan Riechen, Sebastian Worch, Anja Hartmann, Martin Mascher, Uwe Scholz, Kim Baronian, Rüdiger Bode, Frieder Schauer, H Matthias Vorbrodt, Gotthard Kunze
BACKGROUND: The non-conventional yeast Arxula adeninivorans uses 1-butanol as a carbon source and has recently attracted attention as a promising organism for 1-butanol production. Alcohol dehydrogenases (adhp) are important catalysts in 1-butanol metabolism, but only Aadh1p from Arxula has been characterized. This enzyme is involved in ethanol synthesis but has a low impact on 1-butanol degradation. RESULTS: In this study, we identified and characterized a second adhp from A...
October 12, 2016: Microbial Cell Factories
Jie Zhang, Alan R Light, Charles L Hoppel, Caitlin Campbell, Carol J Chandler, Dustin J Burnett, Elaine C Souza, Gretchen A Casazza, Ronald W Hughen, Nancy L Keim, John W Newman, Gary R Hunter, Jose R Fernandez, W Timothy Garvey, Mary-Ellen Harper, Oliver Fiehn, Sean H Adams
With insulin-resistance or type 2 diabetes mellitus, mismatches between mitochondrial fatty acid fuel delivery and oxidative phosphorylation/tricarboxylic acid cycle activity may contribute to inordinate accumulation of short- or medium-chain acylcarnitine fatty acid derivatives (markers of incomplete long-chain fatty acid oxidation [FAO]). We reasoned that incomplete FAO in muscle would be ameliorated concurrent with improved insulin sensitivity and fitness following a ∼14 wk training and weight loss intervention in obese, sedentary, insulin-resistant women...
October 12, 2016: Experimental Physiology
Katsumi Shibata, Momoka Sakamoto
To find a functional biomarker of B-group vitamins, we collected 24-h urine samples from young Japanese women who lived in the community (n=29) to measure branched-chain 2-oxo acids such as 2-oxo-3-methylbutanoic acid, 2-oxo-3-methylpentanoic acid, and 2-oxo-4-methylpentanoic acid because B-group vitamins are involved in the catabolism of branched-chain amino acids. The relationships between each pair of the three urinary 2-oxo acids were very high (2-oxo-3-methylbutanoic acid and 2-oxo-3-methylpentanoic acid, p<0...
2016: Journal of Nutritional Science and Vitaminology
Sara Tulipani, Magali Palau-Rodriguez, Antonio Miñarro Alonso, Fernando Cardona, Anna Marco-Ramell, Bozo Zonja, Miren Lopez de Alda, Araceli Muñoz-Garach, Alejandro Sanchez-Pla, Francisco J Tinahones, Cristina Andres-Lacueva
Metabolomic studies aimed to dissect the connection between the development of type 2 diabetes and obesity are still scarce. In the present study, fasting serum from sixty-four adult individuals classified into four sex-matched groups by their BMI [non-obese versus morbid obese] and the increased risk of developing diabetes [prediabetic insulin resistant state versus non-prediabetic non-insulin resistant] was analyzed by LC- and FIA-ESI-MS/MS-driven metabolomic approaches. Altered levels of [lyso]glycerophospholipids was the most specific metabolic trait associated to morbid obesity, particularly lysophosphatidylcholines acylated with margaric, oleic and linoleic acids [lysoPC C17:0: R=-0...
October 5, 2016: Clinica Chimica Acta; International Journal of Clinical Chemistry
Atsuko Miyagi, Hirofumi Uchimiya, Maki Kawai-Yamada
Carbon dioxide (CO2), nutrient supply, and light quality are amongst the major controlling factors to improve the biomass production and nutritional outputs in plant factory. The present study employed CE-MS to investigate the effects of high CO2, nutrient formulation, and LED on the accumulation of primary metabolites in head lettuce. Results suggested that high CO2 (1000ppm) and nutrient supply enhanced both the biomass and some amino acids. Hierarchical clustering analysis was used to evaluate effects of red LED in combination with high CO2 and Hoagland's formulation; distinctive cluster formation contained 14 amino acids (mostly branched-chain and aromatic amino acids, histidine and arginine)...
March 1, 2017: Food Chemistry
Xiao Wei, Shan Jiang, Yuye Chen, Xiangna Zhao, Huan Li, Weishi Lin, Boxing Li, Xuesong Wang, Jing Yuan, Yansong Sun
BACKGROUND: Intestinal microbiota operated as a whole and was closely related with human health. Previous studies had suggested close relationship between liver cirrhosis (LC) and gut microbiota. METHODS: To determine the functional characteristic of the intestinal microbiota specific for liver cirrhosis, the fecal metaproteome of three LC patients with Child-Turcotte-Pugh (CTP) score of A, B, and C, and their spouse were first compared using high-throughput approach based on denaturing polyacrylamide gel electrophoresis and liquid chromatography-tandem mass spectrometry in our study...
October 4, 2016: BMC Gastroenterology
Laís Rosa Viana, Rafael Canevarolo, Anna Caroline Perina Luiz, Raquel Frias Soares, Camila Lubaczeuski, Ana Carolina de Mattos Zeri, Maria Cristina Cintra Gomes-Marcondes
BACKGROUND: Cachexia is one of the most important causes of cancer-related death. Supplementation with branched-chain amino acids, particularly leucine, has been used to minimise loss of muscle tissue, although few studies have examined the effect of this type of nutritional supplementation on the metabolism of the tumour-bearing host. Therefore, the present study evaluated whether a leucine-rich diet affects metabolomic derangements in serum and tumour tissues in tumour-bearing Walker-256 rats (providing an experimental model of cachexia)...
October 3, 2016: BMC Cancer
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"