Identification of two [4Fe–4S]-cluster-containing hydro-lyases from Pyrococcus furiosus

The hyperthermophilic archaeon Pyrococcus furiosus is a strict anaerobe. It is therefore not expected to use the oxidative tricarboxylic acid (TCA) cycle for energy transduction. Nonetheless, its genome encodes more putative TCA cycle enzymes than the closely related Pyrococcus horikoshii and Pyrococcus abyssi, including an aconitase (PF0201). Furthermore, a two-subunit fumarase (PF1755 and PF1754) is encoded on the Pyr. furiosus genome. In the present study, these three genes were heterologously overexpressed in Escherichia coli to enable characterization of the enzymes. PF1755 and PF1754 were shown to form a [4Fe–4S]-cluster-containing heterodimeric enzyme, able to catalyse the reversible hydratation of fumarate. The aconitase PF0201 also contained an Fe–S cluster, and catalysed the conversion from citrate to isocitrate. The fumarase belongs to the class of two-subunit, [4Fe–4S]-cluster-containing fumarate hydratases exemplified by MmcBC from Pelotomaculum thermopropionicum; the aconitase belongs to the aconitase A family. Aconitase probably plays a role in amino acid synthesis when the organism grows on carbohydrates. However, the function of the seemingly metabolically isolated fumarase in Pyr. furiosus has yet to be established.

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Host nutrient milieu drives an essential role for aspartate biosynthesis during invasiveStaphylococcus aureusinfection

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1922211117 ◽

2020 ◽

Vol 117 (22) ◽

pp. 12394-12401 ◽

Cited By ~ 2

Author(s):

Aimee D. Potter ◽

Casey E. Butrico ◽

Caleb A. Ford ◽

Jacob M. Curry ◽

Irina A. Trenary ◽

...

Keyword(s):

Metabolic Pathways ◽

Aerobic Glycolysis ◽

Bacterial Pathogen ◽

Tca Cycle ◽

Acid Synthesis ◽

Tricarboxylic Acid ◽

Staphylococcal Infection ◽

Amino Acid Synthesis ◽

The Tca Cycle ◽

Host Tissues

The bacterial pathogenStaphylococcus aureusis capable of infecting a broad spectrum of host tissues, in part due to flexibility of metabolic programs.S. aureus, like all organisms, requires essential biosynthetic intermediates to synthesize macromolecules. We therefore sought to determine the metabolic pathways contributing to synthesis of essential precursors during invasiveS. aureusinfection. We focused specifically on staphylococcal infection of bone, one of the most common sites of invasiveS. aureusinfection and a unique environment characterized by dynamic substrate accessibility, infection-induced hypoxia, and a metabolic profile skewed toward aerobic glycolysis. Using a murine model of osteomyelitis, we examined survival ofS. aureusmutants deficient in central metabolic pathways, including glycolysis, gluconeogenesis, the tricarboxylic acid (TCA) cycle, and amino acid synthesis/catabolism. Despite the high glycolytic demand of skeletal cells, we discovered thatS. aureusrequires glycolysis for survival in bone. Furthermore, the TCA cycle is dispensable for survival during osteomyelitis, andS. aureusinstead has a critical need for anaplerosis. Bacterial synthesis of aspartate in particular is absolutely essential for staphylococcal survival in bone, despite the presence of an aspartate transporter, which we identified as GltT and confirmed biochemically. This dependence on endogenous aspartate synthesis derives from the presence of excess glutamate in infected tissue, which inhibits aspartate acquisition byS. aureus. Together, these data elucidate the metabolic pathways required for staphylococcal infection within bone and demonstrate that the host nutrient milieu can determine essentiality of bacterial nutrient biosynthesis pathways despite the presence of dedicated transporters.

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Differential Lowering by Manganese Treatment of Activities of Glycolytic and Tricarboxylic Acid (TCA) Cycle Enzymes Investigated in Neuroblastoma and Astrocytoma Cells Is Associated with Manganese-Induced Cell Death

Neurochemical Research ◽

10.1023/b:nere.0000018841.98399.ce ◽

2004 ◽

Vol 29 (4) ◽

pp. 709-717 ◽

Cited By ~ 38

Author(s):

Gaurangi V. Malthankar ◽

Brenda K. White ◽

Alok Bhushan ◽

Christopher K. Daniels ◽

Kenneth J. Rodnick ◽

...

Keyword(s):

Cell Death ◽

Tca Cycle ◽

Tricarboxylic Acid ◽

Astrocytoma Cells ◽

Tca Cycle Enzymes

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Characterization of the transcriptional response of Candida parapsilosis to the antifungal peptide MAF-1A

PeerJ ◽

10.7717/peerj.9767 ◽

2020 ◽

Vol 8 ◽

pp. e9767

Author(s):

Rong Cheng ◽

Wei Li ◽

Klarke M. Sample ◽

Qiang Xu ◽

Lin Liu ◽

...

Keyword(s):

Antifungal Activity ◽

Candida Parapsilosis ◽

Membrane Integrity ◽

Transcriptional Response ◽

Acid Synthesis ◽

Sterol Synthesis ◽

Antifungal Peptide ◽

Amino Acid Synthesis ◽

Cell Membrane Integrity

Candida parapsilosis is a major fungal pathogen that leads to sepsis. New and more effective antifungal agents are required due to the emergence of resistant fungal strains. MAF-1A is a cationic antifungal peptide isolated from Musca domestica that is effective against a variety of Candida species. However, the mechanism(s) of its antifungal activity remains undefined. Here, we used RNA-seq to identify differentially expressed genes (DEGs) in Candida parapsilosis following MAF-1A exposure. The early (6 h) response included 1,122 upregulated and 1,065 downregulated genes. Late (18 h) responses were associated with the increased expression of 101 genes and the decreased expression of 151 genes. Upon MAF-1A treatment for 18 h, 42 genes were upregulated and 25 genes were downregulated. KEGG enrichment showed that the DEGs in response to MAF-1A were mainly involved in amino acid synthesis and metabolism, oxidative phosphorylation, sterol synthesis, and apoptosis. These results indicate that MAF-1A exerts antifungal activity through interference with Candida parapsilosis cell membrane integrity and organelle function. This provides new insight into the interaction between Candida parapsilosis and this antimicrobial peptide and serves as a reference for future Candida parapsilosis therapies.

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Reductive tricarboxylic acid cycle enzymes and reductive amino acid synthesis pathways contribute to electron balance in a Rhodospirillum rubrum Calvin-cycle mutant

Microbiology ◽

10.1099/mic.0.000877 ◽

2020 ◽

Vol 166 (2) ◽

pp. 199-211 ◽

Cited By ~ 4

Author(s):

Alexandra L. McCully ◽

Maureen C. Onyeziri ◽

Breah LaSarre ◽

Jennifer R. Gliessman ◽

James B. McKinlay

Keyword(s):

Amino Acid ◽

Rhodospirillum Rubrum ◽

Tricarboxylic Acid Cycle ◽

Calvin Cycle ◽

Acid Synthesis ◽

Tricarboxylic Acid ◽

Amino Acid Synthesis ◽

Acid Cycle ◽

Electron Balance ◽

Reductive Tricarboxylic Acid Cycle

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C6-Substituted methanopyrrolidine β-amino acid: synthesis and characterization of oligomeric foldamers

Tetrahedron Letters ◽

10.1016/j.tetlet.2020.152240 ◽

2020 ◽

Vol 61 (35) ◽

pp. 152240

Author(s):

Zilun Hu ◽

Guoliang Lin ◽

Matthew Sender ◽

Kevin C. Cannon ◽

Franklin A. Davis ◽

...

Keyword(s):

Amino Acid ◽

Acid Synthesis ◽

Synthesis And Characterization ◽

Amino Acid Synthesis

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Sesamol Supplementation Mitigates Isoproterenol-Induced Cardiac Toxicity in Rats by Stabilizing Cardiac Mitochondrial and Lysosomal Enzymes

Natural Product Communications ◽

10.1177/1934578x211057940 ◽

2021 ◽

Vol 16 (12) ◽

pp. 1934578X2110579

Author(s):

Lakshmanan Vennila ◽

Kodukkur Viswanathan Pugalendi ◽

Thangaiyan Radhiga

Keyword(s):

Lysosomal Enzymes ◽

Nadh Dehydrogenase ◽

Cardiac Toxicity ◽

Tail Length ◽

Tca Cycle ◽

Tricarboxylic Acid ◽

Tail Moment ◽

Tca Cycle Enzymes ◽

Wistar Strain ◽

Heart Homogenate

The current investigation was intended to evaluate the antimyocardial ischemic effects of sesamol on lactate dehydrogenase (LDH) isoenzymes, DNA damage, and mitochondrial and lysosomal enzyme activities in isoproterenol (ISO)-induced myocardial infarction (MI) in male albino Wistar strain rats. Rats that received ISO (85 mg/kg body weight (B.W) subcutaneously) for the first 2 consecutive days showed significant reduction in the activities of tricarboxylic acid (TCA) cycle enzymes (isocitrate dehydrogenase, α-ketoglutarate dehydrogenase, malate dehydrogenase, and succinate dehydrogenase) and respiratory chain enzymes (cytochrome c oxidase and nicotinamide adenine dinucleotide hydrogen (NADH) dehydrogenase) in the heart mitochondria. The activities of the lysosomal enzymes (α-and β-glucosidases, α and β-galactosidases, β-glucuronidase and β-N-acetyl glucosaminidase and cathepsin-B and cathepsin-D) were increased significantly in the heart homogenate of ISO-induced MI rats. ISO injection also increased the % of tail DNA, tail length, and tail moment and decreased the % of head DNA. Pretreatment with sesamol (50 mg/kg B.W) every day for a period of 9 days prevented the above abnormalities induced by ISO. In conclusion, it can be inferred that administration of sesamol has a potent beneficial role against ISO-induced damage to the mitochondria, lysosomes, and DNA, thereby preventing MI.

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Characterization of d-succinylase from Cupriavidus sp. P4-10-C and its application in d-amino acid synthesis

Journal of Bioscience and Bioengineering ◽

10.1016/j.jbiosc.2017.10.007 ◽

2018 ◽

Vol 125 (3) ◽

pp. 282-286 ◽

Cited By ~ 3

Author(s):

Yosuke Sumida ◽

Sachio Iwai ◽

Yoshiaki Nishiya ◽

Shinya Kumagai ◽

Toshihide Yamada ◽

...

Keyword(s):

Amino Acid ◽

Acid Synthesis ◽

Amino Acid Synthesis

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Reductive TCA cycle enzymes and reductive amino acid synthesis pathways contribute to electron balance in aRhodospirillum rubrumCalvin cycle mutant

10.1101/614065 ◽

2019 ◽

Author(s):

Alexandra L. McCully ◽

Maureen C. Onyeziri ◽

Breah LaSarre ◽

Jennifer R. Gliessman ◽

James B. McKinlay

Keyword(s):

Amino Acids ◽

Calvin Cycle ◽

Tca Cycle ◽

Electron Acceptors ◽

Organic Substrates ◽

Amino Acid Synthesis ◽

Electron Balance ◽

Tca Cycle Enzymes ◽

Electron Carriers ◽

Dependent Pathway

AbstractPurple nonsulfur bacteria (PNSB) use light for energy and organic substrates for carbon and electrons when growing photoheterotrophically. This lifestyle generates more reduced electron carriers than are required for biosynthesis, even during consumption of some of the most oxidized organic substrates like malate and fumarate. Excess reduced electron carriers must be oxidized for photoheterotrophic growth to occur. Diverse PNSB commonly rely on the CO2-fixing Calvin cycle to oxidize excess reduced electron carriers. Some PNSB also produce H2or reduce terminal electron acceptors as alternatives to the Calvin cycle.Rhodospirillum rubrumCalvin cycle mutants defy this trend by growing phototrophically on malate or fumarate without H2production or access to terminal electron acceptors. We used13C-tracer experiments to examine how aRs. rubrumCalvin cycle mutant maintains electron balance under such conditions. We detected the reversal of some TCA cycle enzymes, which carried reductive flux from malate or fumarate to α-ketoglutarate. This pathway and the reductive synthesis of amino acids derived from α-ketoglutarate are likely important for electron balance, as supplementing the growth medium with α-ketoglutarate-derived amino acids preventedRs. rubrumCalvin cycle mutant growth unless a terminal electron acceptor was provided. Flux estimates also suggested that the Calvin cycle mutant preferentially synthesized isoleucine using the reductive threonine-dependent pathway instead of the less-reductive citramalate-dependent pathway. Collectively, our results suggest that alternative biosynthetic pathways can contribute to electron balance within the constraints of a relatively constant biomass composition.

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