De novo pathway is an active metabolic pathway of cysteine synthesis in Haemonchus contortus

ABSTRACT De novo pyrimidine biosynthesis is a key metabolic pathway involved in multiple biosynthetic processes. Here, we identified an original series of 3-(1H-indol-3-yl)-2,3-dihydro-4H-furo[3,2-c]chromen-4-one derivatives as a new class of pyrimidine biosynthesis inhibitors formed by two edge-fused polycyclic moieties. We show that identified compounds exhibit broad-spectrum antiviral activity and immunostimulatory properties, in line with recent reports linking de novo pyrimidine biosynthesis with innate defense mechanisms against viruses. Most importantly, we establish that pyrimidine deprivation can amplify the production of both type I and type III interferons by cells stimulated with retinoic acid-inducible gene 1 (RIG-I) ligands. Altogether, our results further expand the current panel of pyrimidine biosynthesis inhibitors and illustrate how the production of antiviral interferons is tightly coupled to this metabolic pathway. Functional and structural similarities between this new chemical series and dicoumarol, which was reported before to inhibit pyrimidine biosynthesis at the dihydroorotate dehydrogenase (DHODH) step, are discussed.

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Recent Advances in Microbial Production of cis,cis-Muconic Acid

Biomolecules ◽

10.3390/biom10091238 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1238 ◽

Cited By ~ 1

Author(s):

Sisun Choi ◽

Han-Na Lee ◽

Eunhwi Park ◽

Sang-Jong Lee ◽

Eung-Soo Kim

Keyword(s):

Metabolic Pathway ◽

Aromatic Compounds ◽

Terephthalic Acid ◽

De Novo ◽

Vital Role ◽

Chemical Processes ◽

Muconic Acid ◽

Production Strategies ◽

Culture Process ◽

Foreign Genes

cis,cis-Muconic acid (MA) is a valuable C6 dicarboxylic acid platform chemical that is used as a starting material for the production of various valuable polymers and drugs, including adipic acid and terephthalic acid. As an alternative to traditional chemical processes, bio-based MA production has progressed to the establishment of de novo MA pathways in several microorganisms, such as Escherichia coli, Corynebacterium glutamicum, Pseudomonas putida, and Saccharomyces cerevisiae. Redesign of the metabolic pathway, intermediate flux control, and culture process optimization were all pursued to maximize the microbial MA production yield. Recently, MA production from biomass, such as the aromatic polymer lignin, has also attracted attention from researchers focusing on microbes that are tolerant to aromatic compounds. This paper summarizes recent microbial MA production strategies that involve engineering the metabolic pathway genes as well as the heterologous expression of some foreign genes involved in MA biosynthesis. Microbial MA production will continue to play a vital role in the field of bio-refineries and a feasible way to complement various petrochemical-based chemical processes.

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Functional consequences of mitochondrial proteome heterogeneity

AJP Cell Physiology ◽

10.1152/ajpcell.00109.2006 ◽

2007 ◽

Vol 292 (2) ◽

pp. C698-C707 ◽

Cited By ~ 74

Author(s):

D. Thor Johnson ◽

Robert A. Harris ◽

Paul V. Blair ◽

Robert S. Balaban

Keyword(s):

Metabolic Pathway ◽

De Novo ◽

Functional Domain ◽

Specific Information ◽

Urea Synthesis ◽

Protein Distribution ◽

Mitochondrial Proteome ◽

Coa Transferase ◽

Functional Consequences ◽

The Impact

Potential functional consequences of the differences in protein distribution between the mitochondria of the rat liver, heart, brain, and kidney, as determined in the companion paper in this issue (Johnson DT, French S, Blair PV, You JS, Bemis KG, Wang M, Harris RA, and Balaban RS. The tissue heterogeneity of the mammalian mitochondrial proteome. Am J Physiol Cell Physiol292: C689–C697, 2006), were analyzed using a canonical metabolic pathway approach as well as a functional domain homology analysis. These data were inserted into the Kyoto Encyclopedia of Genes and Genomes pathway framework to give global and metabolic pathway-specific information on the impact of the differential protein distribution on mitochondrial function. Custom pathway analysis was also performed using pathways limited to the mitochondrion. With the use of this approach, several well-known functional differences between these mitochondrial populations were confirmed. These included GABA metabolism in the brain, urea synthesis in the liver, and the domination of oxidative phosphorylation in the heart. By comparing relative protein amounts of mitochondria across tissues, a greater understanding of functional emphasis is possible as well as the nuclear “programming” required to enhance a given function within the mitochondria. For proteins determined to be mitochondrial and lacking a defined role functional domain BLAST analyses were performed. Several proteins associated with DNA structural modification and a novel CoA transferase were identified. A protein was also identified capable of catalyzing the first three steps of de novo pyrimidine synthesis. This analysis demonstrates that the distribution of nuclear encoded proteins significantly modifies the overall functional emphasis of the mitochondria to meet tissue-specific needs. These studies demonstrate the existence of mitochondrial biochemical functions that at present are poorly defined.

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EXTH-04. BLOCKADE OF NRF2/GLUTATHIONE METABOLISM AS A SYNTHETIC LETHALITY APPROACH FOR IDH1-MUTATED GLIOMA

Neuro-Oncology ◽

10.1093/neuonc/noz175.338 ◽

2019 ◽

Vol 21 (Supplement_6) ◽

pp. vi83-vi83

Author(s):

Yang Liu ◽

Yanxin Lu ◽

Orieta Celiku ◽

Aiguo Li ◽

Chunzhang Yang

Keyword(s):

Tumor Cell ◽

Metabolic Pathway ◽

De Novo ◽

Synthetic Lethality ◽

Substantial Reduction ◽

Lower Grade ◽

Related Factor ◽

De Novo Synthesis ◽

Antioxidant Genes ◽

Cox Regression Analysis

Abstract BACKGROUND Mutations in isocitrate dehydrogenase (IDH1/2) are frequent genetic abnormalities in human malignancies. IDH1/2-mutated cancers are a recently defined disease entity with distinctive patterns of tumor cell biology, metabolism and resistance to therapy. Molecular targeting approaches against this disease cluster remain limited. METHODS We investigated the redox homeostasis in IDH1 mutant-transduced cells and patient-derived brain tumor initiating cells. The importance of antioxidant genes was confirmed through COX regression analysis on a large cohort of lower grade glioma. We investigated the biologic impact of Nuclear factor erythroid 2-related factor 2 (NRF2) on the glutathione de novo synthesis in IDH1-mutated cells. Finally, we evaluated the value of targeting NRF2/glutathione metabolic pathway as a potential synthetic lethality approach for IDH1-mutated cell in vitro and in vivo. RESULTS We discovered that acquisition of cancer-associated IDH1 mutants results in constitutive activation of NRF2-governed cytoprotective pathways through decoupling of NRF2 from its E3 ligase Kelch-like ECH-associated protein 1. NRF2 mediated the transcriptional activation of GCLC, GCLM and SLC7A11, which strengthens the glutathione de novo synthesis, and relieves the metabolic burden derived from IDH1 mutant neomorphic activity. Blockade of the NRF2/glutathione metabolic pathway synergizes with the elevated intrinsic reactive oxygen species, which results in overwhelming oxidative damage in IDH1-mutated cells, as well as a substantial reduction in tumor cell proliferation and xenograft expansion. CONCLUSION Our findings suggest that blockade of the NRF2/glutathione synthetic pathway is a novel targeting strategy for IDH1-mutated malignancies.

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Extensive genomic and transcriptomic variation defines the chromosome-scale assembly of Haemonchus contortus, a model gastrointestinal worm

10.1101/2020.02.18.945246 ◽

2020 ◽

Cited By ~ 2

Author(s):

Stephen R. Doyle ◽

Alan Tracey ◽

Roz Laing ◽

Nancy Holroyd ◽

David Bartley ◽

...

Keyword(s):

Genome Assembly ◽

Haemonchus Contortus ◽

Vaccine Development ◽

De Novo ◽

Anthelmintic Resistance ◽

Draft Genome ◽

Small Ruminants ◽

High Quality ◽

Long Read ◽

Genome Assemblies

AbstractBackgroundHaemonchus contortus is a globally distributed and economically important gastrointestinal pathogen of small ruminants, and has become the key nematode model for studying anthelmintic resistance and other parasite-specific traits among a wider group of parasites including major human pathogens. Two draft genome assemblies for H. contortus were reported in 2013, however, both were highly fragmented, incomplete, and differed from one another in important respects. While the introduction of long-read sequencing has significantly increased the rate of production and contiguity of de novo genome assemblies broadly, achieving high quality genome assemblies for small, genetically diverse, outcrossing eukaryotic organisms such as H. contortus remains a significant challenge.ResultsHere, we report using PacBio long read and OpGen and 10X Genomics long-molecule methods to generate a highly contiguous 283.4 Mbp chromosome-scale genome assembly including a resolved sex chromosome. We show a remarkable pattern of almost complete conservation of chromosome content (synteny) with Caenorhabditis elegans, but almost no conservation of gene order. Long-read transcriptome sequence data has allowed us to define coordinated transcriptional regulation throughout the life cycle of the parasite, and refine our understanding of cis- and trans-splicing relative to that observed in C. elegans. Finally, we use this assembly to give a comprehensive picture of chromosome-wide genetic diversity both within a single isolate and globally.ConclusionsThe H. contortus MHco3(ISE).N1 genome assembly presented here represents the most contiguous and resolved nematode assembly outside of the Caenorhabditis genus to date, together with one of the highest-quality set of predicted gene features. These data provide a high-quality comparison for understanding the evolution and genomics of Caenorhabditis and other nematodes, and extends the experimental tractability of this model parasitic nematode in understanding pathogen biology, drug discovery and vaccine development, and important adaptive traits such as drug resistance.

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CSIG-02. NRF2-GUIDED GLUTATHIONE SYNTHESIS IS AN ESSENTIAL METABOLIC PATHWAY IN IN IDH1-MUTATED GLIOMA

Neuro-Oncology ◽

10.1093/neuonc/noab196.128 ◽

2021 ◽

Vol 23 (Supplement_6) ◽

pp. vi33-vi33

Author(s):

Yang Liu ◽

Di Yu ◽

Chunzhang Yang

Keyword(s):

Metabolic Pathway ◽

Nicotinamide Adenine Dinucleotide ◽

De Novo ◽

Redox Homeostasis ◽

Nicotinamide Adenine ◽

De Novo Synthesis ◽

Who Grade ◽

Glutathione Synthesis ◽

Synergistic Cytotoxicity ◽

Idh Mutations

Abstract BACKGROUND Isocitrate dehydrogenase (IDH) mutations are common genetic abnormalities in WHO Grade II/III glioma, which result in the reprogramming of cellular metabolism and redox homeostasis. Many lines of evidence showed that IDH mutations are critical for glioma formation, whereas the therapeutic options for IDH-mutated cancers remain limited. METHODS In the present study, we used the patient-derived glioma cell lines to investigate the role of nuclear factor erythroid 2-related factor 2 (NRF2) governed glutathione de novo synthesis. Further, we evaluated the therapeutic value of NRF2 inhibitors in IDH1-mutated cells and preclinical orthotopic models. RESULTS The neomorphic activity of mutant IDH reprogrammed the metabolic pathways involving enzyme cofactors such as nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP). The depletion of NAD(P) in IDH1-mutated cells resulted in elevated oxidative stress and constitutive activation of NRF2-governed cytoprotective pathways through the decoupling of NRF2 from its E3 ligase Kelch-like ECH-associated protein 1 (Keap1). Activation of NRF2 enhanced glutathione synthesis by enhancing the gene transcription of GCLC, GCLM, and SLC7A11, which are the critical for glutathione de novo synthesis. Further, evidence from both in vitro assays and patient cohort indicated that NRF2 governed glutathione synthesis is important for maintaining the redox homeostasis and cell survival, especially in IDH1-mutated glioma. Finally, Blockade of the NRF2/glutathione metabolic pathway exhibited synergistic cytotoxicity with the metabolic stress in IDH1-mutated cells, which results in overwhelming oxidative damage, as well as a substantial reduction in tumor cell proliferation and xenograft expansion. CONCLUSION In this study, we highlighted that NRF2 plays critical roles in the disease progression of IDH1-mutated glioma by prompting glutathione synthesis. Targeting NRF2 governed glutathione metabolism could serve as a valuable synthetic lethality approach for IDH1-mutated malignancies.

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Energy metabolism in the developing larval stages of Ancylostoma tubaeforme and Haemonchus contortus: glycolytic and tncarboxylic acid cycle enzymes

Parasitology ◽

10.1017/s0031182000049118 ◽

1985 ◽

Vol 90 (1) ◽

pp. 169-177 ◽

Cited By ~ 4

Author(s):

C. O. E. Onwuliri

Keyword(s):

Energy Metabolism ◽

Pyruvate Kinase ◽

Metabolic Pathway ◽

Haemonchus Contortus ◽

Phosphoenolpyruvate Carboxykinase ◽

Tricarboxylic Acid Cycle ◽

Tricarboxylic Acid ◽

Aconitate Hydratase ◽

Acid Cycle ◽

Infective Larvae

The activities of glycolytic and related enzymes and the tricarboxylic acid cycle enzymes were measured in freshly isolated 1st- (Li), 2nd- (L2) and 3rd-stage (L3) larvae of both Ancylostoma tubaeforme and Haemonchus contortus. All enzymes of the glycolytic pathway were present in all developmental stages of both strongylid nematodes although higher levels of activities were obtained in the pre-infective 1st- and 2nd-stage larvae than in the infective 3rd stage. However, the pre-infective larvae contained lower levels of pyruvate kinase (PK) than the infective larvae. Consequently, the pyruvate kinase to phosphoenolpyruvate carboxykinase (PEPCK) ratios were 0·23 and 0·26 for the L1s and L2s for A. tubaeforme and 0·36 and 0·21 for those of H. contortus respectively. High levels of activity of glucose-6-phosphate dehydrogenase obtained in the bacteriophagous pre-infective larvae were consistent with high rates of morphogenesis and substrate synthesis characteristic of the pre-infective stages. All the tricarboxylic acid cycle enzymes were present in the infective larvae of both nematodes while in the pre-infective Li and L2 stages, the enzymes at the beginning of the cycle, namely aconitate hydratase and NAD-linked isocitrate dehydrogenase, were not detected. A scheme was proposed for the energy metabolism of these developing larvae. In this scheme, the pre-infective larvae were shown to operate an anaerobic metabolic pathway involving the carboxylation of phosphoenolpyruvate (PEP) by phosphoenolpyru vate carboxykinase (PEPCK) to form oxaloacetate (OAA), whereas in the infective larvae the metabolic pathway favouring the direct dephosphorylation of PEP, as in vertebrate tissues, was followed.

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