Read by QxMD icon Read

Pentose Phosphate Pathway

Christopher P Long, Jacqueline E Gonzalez, Robert M Cipolla, Maciek R Antoniewicz
Vibrio natriegens is a fast-growing, non-pathogenic bacterium that is being considered as the next-generation workhorse for the biotechnology industry. However, little is known about the metabolism of this organism which is limiting our ability to apply rational metabolic engineering strategies. To address this critical gap in current knowledge, here we have performed a comprehensive analysis of V. natriegens metabolism. We constructed a detailed model of V. natriegens core metabolism, measured the biomass composition, and performed high-resolution (13)C metabolic flux analysis ((13)C-MFA) to estimate intracellular fluxes using parallel labeling experiments with the optimal tracers [1,2-(13)C]glucose and [1,6-(13)C]glucose...
October 14, 2017: Metabolic Engineering
Chang Liu, Bao Liu, Er-Long Zhang, Wen-Ting Liao, Jie Liu, Bing-Da Sun, Gang Xu, Jian Chen, Yu-Qi Gao
As a typical model of hypoxia‑induced excessive erythrocytosis, high altitude polycythemia (HAPC) results in microcirculation disturbance, aggravates tissue hypoxia and results in a severe clinical outcome, without any effective intervention methods except for returning to an oxygen‑rich environment. The present study aimed to explore potential therapeutic targets which may participate in the recovery of HAPC by studying the mechanisms of reducing the hemoglobin (HB) concentration during re‑oxygenation...
October 17, 2017: Molecular Medicine Reports
Lauren T Cordova, Robert M Cipolla, Adti Swarup, Christopher P Long, Maciek R Antoniewicz
Thermophilic organisms are being increasingly investigated and applied in metabolic engineering and biotechnology. The distinct metabolic and physiological characteristics of thermophiles, including broad substrate range and high uptake rates, coupled with recent advances in genetic tool development, present unique opportunities for strain engineering. However, poor understanding of the cellular physiology and metabolism of thermophiles has limited the application of systems biology and metabolic engineering tools to these organisms...
October 13, 2017: Metabolic Engineering
Zhongyang Qiu, Qiuqiang Gao, Jie Bao
Xylose-assimilating pathways were constructed in the parental Pediococcus acidilactici strain and evolutionarily adapted to yield a highly stable co-fermentation strain for l-lactic acid production. The phosphoketolase pathway (PK) was blocked for reduction of acetic acid generation by disrupting phosphoketolase (pkt) gene. The pentose phosphate pathway (PPP) was reconstructed for xylose assimilation by integrating four heterologous genes encoding transketolase (tkt), transaldolase (tal), xylose isomerase (xylA) and xylulokinase (xylB) into the P...
September 21, 2017: Bioresource Technology
Heng-Gang Yang, Huan Zhao, Jiao-Jiao Li, Shao-Meng Chen, Lang-Ming Mou, Jian Zou, Guo-Dong Chen, Sheng-Ying Qin, Chuan-Xi Wang, Dan Hu, Xin-Sheng Yao, Hao Gao
Phyllomeroterpenoids A-C (1-3), multi-biosynthetic pathway derived meroterpenoids from amino acid/pentose phosphate/terpenoid pathways, were isolated from the TCM endophytic fungus Phyllosticta sp. J13-2-12Y, together with six biosynthetically related compounds (4-9). All structures were determined by extensive spectroscopic analysis, chemical derivatization, and ECD experiments. A plausible biosynthetic pathway of 1-3 was proposed. In addition, the antimicrobial activities of all isolated compounds were evaluated against Staphylococcus aureus 209P (bacterium) and Candida albicans FIM709 (fungus)...
October 10, 2017: Scientific Reports
Cedric Simillion, Nasser Semmo, Jeffrey R Idle, Diren Beyoğlu
About one in 15 of the world's population is chronically infected with either hepatitis virus B (HBV) or C (HCV), with enormous public health consequences. The metabolic alterations caused by these infections have never been directly compared and contrasted. We investigated groups of HBV-positive, HCV-positive, and uninfected healthy controls using gas chromatography-mass spectrometry analyses of their plasma and urine. A robust regression analysis of the metabolite data was conducted to reveal correlations between metabolite pairs...
October 8, 2017: Metabolites
Shao Thing Teoh, Sophia Y Lunt
Metabolic changes accompany tumor progression and metastatic dissemination of cancer cells. Yet, until recently, metabolism has received little attention in the study of cancer metastasis. Cancer cells undergo significant metabolic rewiring as they acquire metastatic traits and adapt to survive in multiple environments with varying nutrient availability, oxygen concentrations, and extracellular signals. Therefore, to effectively treat metastatic cancer, it is important to understand the metabolic strategies adopted by cancer cells during the metastatic process...
October 9, 2017: Wiley Interdisciplinary Reviews. Systems Biology and Medicine
Marta Gómez de Cedrón, Rebeca Acín Pérez, Ruth Sánchez-Martínez, Susana Molina, Jesús Herranz, Jaime Feliu, Guillermo Reglero, Jose Antonio Enríquez, Ana Ramírez de Molina
Cancer cell survival and metastasis are dependent on metabolic reprogramming that is capable of increasing resistance to oxidative and energetic stress. Targeting these two processes can be crucial for cancer progression. Herein, we describe the role of microRNA-661 (miR661) as epigenetic regulator of colon cancer (CC) cell metabolism. miR661 induces a global increase in reactive oxygen species (ROS), specifically in mitochondrial superoxide anions (SO(-) ), which appears to be mediated by decreased carbohydrate metabolism and pentose phosphate pathway, and by a higher dependency on mitochondrial respiration...
October 5, 2017: Molecular Oncology
Haymanti Bhanot, Ellen L Weisberg, Mamatha M Reddy, Atsushi Nonami, Donna Neuberg, Richard M Stone, Klaus Podar, Ravi Salgia, James D Griffin, Martin Sattler
Acute myeloid leukemia (AML) cells are highly dependent on glycolytic pathways to generate metabolic energy and support cell growth, hinting at specific, targetable vulnerabilities as potential novel targets for drug development. Elevated levels of NADPH, a central metabolic factor involved in redox reactions, are common in myeloid leukemia cells, but the significance or biochemical basis underlying this increase is unknown. Using a small molecule analog that efficiently inhibits NADPH-producing enzymes, we found that AML cells require NADPH homeostasis for cell growth...
September 15, 2017: Oncotarget
J J Fan, J J Bai, D M Ma, L Y Yu, P Jiang
Aldolase is a key enzyme involved in glycolysis, gluconeogenesis, and the pentose phosphate pathway. To establish the expression patterns of all three aldolase isozyme genes in different tissues and during early embryogenesis in lower vertebrates, as well as to explore the functional differences between these three isozymes, the grass carp was selected as a model owing to its relatively high glucose-metabolizing capability. Based on the cDNA sequences of the aldolase A, B, and C genes, the expression patterns of these three isozymes were analyzed in different tissues and during early embryogenesis using quantitative real-time polymerase chain reaction (qRT-PCR)...
September 27, 2017: Genetics and Molecular Research: GMR
Stephen Chapman, Marcelo Trindade Dos Santos, Giles N Johnson, Mauricio V Kritz, Jean-Marc Schwartz
The regulation of metabolic networks has been shown to be distributed and shared through the action of metabolic cycles. Biochemical cycles play important roles in maintaining flux and substrate availability for multiple pathways to supply cellular energy and contribute to dynamic stability. By understanding the cyclic and acyclic flows of matter through a network, we are closer to understanding how complex dynamic systems distribute flux along interconnected pathways. In this work, we have applied a cycle decomposition algorithm to a genome-scale metabolic model of Chlamydomonas reinhardtii to analyse how acetate supply affects the distribution of fluxes that sustain cellular activity...
September 29, 2017: Bio Systems
Anna-Luisa Thiepold, Nadja I Lorenz, Martha Foltyn, Anna L Engel, Iris Divé, Hans Urban, Sonja Heller, Ines Bruns, Ute Hofmann, Stefan Dröse, Patrick N Harter, Michel Mittelbronn, Joachim P Steinbach, Michael W Ronellenfitsch
Glioblastomas are characterized by fast uncontrolled growth leading to hypoxic areas and necrosis. Signalling from EGFR via mammalian target of rapamycin complex 1 (mTORC1) is a major driver of cell growth and proliferation and one of the most commonly altered signalling pathways in glioblastomas. Therefore, epidermal growth factor receptor and mTORC1 signalling are plausible therapeutic targets and clinical trials with inhibitors are in progress. However, we have previously shown that epidermal growth factor receptor and mTORC1 inhibition triggers metabolic changes leading to adverse effects under the conditions of the tumour microenvironment by protecting from hypoxia-induced cell death...
October 1, 2017: Brain: a Journal of Neurology
Wenlan Liu, Zhirong Sun, Jixu Qu, Chunning Yang, Xiaomin Zhang, Xinxin Wei
The aim of the present study was to investigate the correlation between root respiration and the levels of biomass and glycyrrhizic acid in Glycyrrhiza uralensis. Root respiration was determined using a biological oxygen analyzer. Respiration-related enzymes including glucose-6-phosphate dehydrogenase plus 6-phosphogluconate dehydrogenase, phosphohexose isomerase and succinate dehydrogenase, and respiratory pathways were evaluated. Biomass was determined by a drying-weighing method. In addition, the percentage of glycyrrhizic acid was detected using high-performance liquid chromatography...
September 2017: Experimental and Therapeutic Medicine
Stephanie C Morriss, Xiaoyi Liu, Brice E Floyd, Diane C Bassham, Gustavo C MacIntosh
Background and Aims: Enzymes belonging to the RNase T2 family are essential for normal rRNA turnover in eukaryotes. In Arabidopsis thaliana, this function is performed by RNS2. The null mutant rns2-2 has increased rRNA half-life and constitutive autophagy. The aim of this work was to determine the molecular changes that take place in the rns2-2 mutant that may lead to altered cellular homeostasis, manifested by the observed cellular phenotype. Methods: To determine the effect of defective rRNA turnover on cellular homeostasis, comparative transcriptome and metabolome analyses of 10-day-old wild-type and rns2-2 seedlings were used to identify molecular processes affected in the mutant...
September 14, 2017: Annals of Botany
Tracy Youngster, Julie A Wushensky, Ludmilla Aristilde
We investigated the co-catabolism of carbohydrate mixtures in Bacillus megaterium QM B1551 using a (13)C-assisted metabolomics profiling approach. Specifically, we monitored the ability of B. megaterium to achieve the simultaneous catabolism of glucose and a common disaccharide - cellobiose, maltose, or sucrose. Growth experiments indicated that each disaccharide alone can serve as a sole carbon source for B. megaterium, in accordance with the genetic analysis of this bacterium, which predicted diverse metabolic capabilities...
September 28, 2017: Microbiology
K Usami, A Okamoto
One of the possible synthetic routes to pentoses is the formose reaction pathway from C1 and C2 carbon sources, but preferential ribose generation in a one-pot reaction without any control of conditions has not been reported. We have tested a one-pot pentose formation and analyzed the products and mechanism in the reaction, using (1)H-NMR and mass spectrometry. Hydroxyapatite (HAp), which consists of phosphate and calcium ions, worked continuously for cross-aldol reactions and Lobry de Bruyn-van Ekenstein transformations to yield ribose from formaldehyde and glycolaldehyde...
September 27, 2017: Organic & Biomolecular Chemistry
Timothy P Driscoll, Victoria I Verhoeve, Mark L Guillotte, Stephanie S Lehman, Sherri A Rennoll, Magda Beier-Sexton, M Sayeedur Rahman, Abdu F Azad, Joseph J Gillespie
Reductive genome evolution has purged many metabolic pathways from obligate intracellular Rickettsia (Alphaproteobacteria; Rickettsiaceae). While some aspects of host-dependent rickettsial metabolism have been characterized, the array of host-acquired metabolites and their cognate transporters remains unknown. This dearth of information has thwarted efforts to obtain an axenic Rickettsia culture, a major impediment to conventional genetic approaches. Using phylogenomics and computational pathway analysis, we reconstructed the Rickettsia metabolic and transport network, identifying 51 host-acquired metabolites (only 21 previously characterized) needed to compensate for degraded biosynthesis pathways...
September 26, 2017: MBio
Neil Templeton, Sen Xu, David J Roush, Hao Chen
Industrial cell culture requires substantial energy to generate protein. The protein generated is not only the product of interest (IgG in this case), but also the protein associated with biomass. Here, (13)C-Metabolic Flux Analysis ((13)C-MFA) was utilized to compare the stationary phase of a fed-batch process to a perfusion process producing the same product by the same clone. The fed-batch process achieved significantly higher specific productivity, approximately 60% greater than the perfusion process. In spite of this, a general lack of difference was observed when globally comparing glycolysis, pentose phosphate pathway, and TCA cycle fluxes...
September 22, 2017: Metabolic Engineering
Katarína Chalásová, Lukáš Pácal, Anna Pleskačová, Lucia Knopfová, Jitka Řehořová, Marie Tomandlová, Josef Tomandl, Kateřina Kaňková
Aim Pentose phosphate pathway (PPP) with key enzyme transketolase (TKT), represents a potentially 'protective' mechanism in hyperglycaemia. Diabetic kidney disease (DKD), a common complication of both type 1 and type 2 diabetes associated with significant morbidity and mortality, represents the most common cause of chronic kidney disease (CKD). We hypothesized that protective PPP action in diabetes and eventually even more severely in concomitant DKD might be compromised by limited intracellular availability of an active TKT cofactor thiamine diphosphate (TDP)...
September 26, 2017: Experimental and Clinical Endocrinology & Diabetes
Xiaofei Wang, Haiyan Han, Zhihui Lv, Zhiwei Lin, Yongpeng Shang, Tao Xu, Yang Wu, Ying Zhang, Di Qu
PhoU, a conserved protein that has been proposed to coordinate phosphate import, is a negative regulator of drug tolerance in most bacteria. In Staphylococcus epidermidis, the role of PhoU in biofilm formation and drug tolerance has not yet been investigated. Two PhoU homologs in the genome of S. epidermidis have been identified by the presence of the conserved motif [(E(D)XXXD] of PhoU. We separately constructed ΔphoU1 and ΔphoU2 of S. epidermidis 1457 strain. The ΔphoU2 displayed growth retardation, weakened biofilm formation capacity, higher sensitivity to H2O2 and reduced tolerance to multiple antibiotics...
September 25, 2017: Journal of Bacteriology
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"