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Scheidig AJ, Horvath D, Szedlacsek SE. Crystal structure of a xylulose 5-phosphate phosphoketolase. Insights into the substrate specificity for xylulose 5-phosphate. J Struct Biol 2019; 207:85-102. [PMID: 31059775 DOI: 10.1016/j.jsb.2019.04.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 04/25/2019] [Accepted: 04/26/2019] [Indexed: 12/11/2022]
Abstract
Phosphoketolases (PK) are TPP-dependent enzymes which play essential roles in carbohydrate metabolism of numerous bacteria. Depending on the substrate specificity PKs can be subdivided into xylulose 5-phosphate (X5P) specific PKs (XPKs) and PKs which accept both X5P and fructose 6-phosphate (F6P) (XFPKs). Despite their key metabolic importance, so far only the crystal structures of two XFPKs have been reported. There are no reported structures for any XPKs and for any complexes between PK and substrate. One of the major unknowns concerning PKs mechanism of action is related to the structural determinants of PKs substrate specificity for X5P or F6P. We report here the crystal structure of XPK from Lactococcus lactis (XPK-Ll) at 2.1 Å resolution. Using small angle X-ray scattering (SAXS) we proved that XPK-Ll is a dimer in solution. Towards better understanding of PKs substrate specificity, we performed flexible docking of TPP-X5P and TPP-F6P on crystal structures of XPK-Ll, two XFPKs and transketolase (TK). Calculated structure-based binding energies consistently support XPK-Ll preference for X5P. Analysis of structural models thus obtained show that substrates adopt moderately different conformation in PKs active sites following distinct networks of polar interactions. Based on the here reported structure of XPK-Ll we propose the most probable amino acid residues involved in the catalytic steps of reaction mechanism. Altogether our results suggest that PKs substrate preference for X5P or F6P is the outcome of a fine balance between specific binding network and dissimilar catalytic residues depending on the enzyme (XPK or XFPK) - substrate (X5P or F6P) couples.
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Affiliation(s)
- A J Scheidig
- Structural Biology, Zoological Institute, Kiel University, Am Botanischen Garten 1-9, 24118 Kiel, Germany.
| | - D Horvath
- Laboratoire de Chémoinformatique, UMR 7140 CNRS-Université de Strasbourg, 1 rue Blaise Pascal, Strasbourg 67000, France.
| | - S E Szedlacsek
- Department of Enzymology, Institute of Biochemistry of the Romanian Academy, Spl. Independentei 296, Bucharest 060031, Romania.
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Brooke DG, van Dam EM, Watts CKW, Khoury A, Dziadek MA, Brooks H, Graham LJK, Flanagan JU, Denny WA. Targeting the Warburg Effect in cancer; relationships for 2-arylpyridazinones as inhibitors of the key glycolytic enzyme 6-phosphofructo-2-kinase/2,6-bisphosphatase 3 (PFKFB3). Bioorg Med Chem 2013; 22:1029-39. [PMID: 24398380 DOI: 10.1016/j.bmc.2013.12.041] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Revised: 12/05/2013] [Accepted: 12/17/2013] [Indexed: 12/15/2022]
Abstract
High-throughput screening of a small-molecule library identified a 5-triazolo-2-arylpyridazinone as a novel inhibitor of the important glycolytic enzyme 6-phosphofructo-2-kinase/2,6-bisphosphatase 3 (PFKFB3). Such inhibitors are of interest due to PFKFB3's control of the important glycolytic pathway used by cancer cells to generate ATP. A series of analogues was synthesized to study structure-activity relationships key to enzyme inhibition. Changes to the triazolo or pyridazinone rings were not favoured, but limited-size substitutions on the aryl ring provided modest increases in potency against the enzyme. Selected analogues and literature-described inhibitors were evaluated for their ability to suppress the glycolytic pathway, as detected by a decrease in lactate production, but none of these compounds demonstrated such suppression at non-cytotoxic concentrations.
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Affiliation(s)
- Darby G Brooke
- Auckland Cancer Society Research Centre, School of Medical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Ellen M van Dam
- Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, Sydney, NSW 2010, Australia
| | - Colin K W Watts
- Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, Sydney, NSW 2010, Australia
| | - Amanda Khoury
- Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, Sydney, NSW 2010, Australia
| | - Marie A Dziadek
- Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, Sydney, NSW 2010, Australia
| | - Hilary Brooks
- Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, Sydney, NSW 2010, Australia
| | - Lisa-Jane K Graham
- Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, Sydney, NSW 2010, Australia
| | - Jack U Flanagan
- Auckland Cancer Society Research Centre, School of Medical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - William A Denny
- Auckland Cancer Society Research Centre, School of Medical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
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Funato Y, Hayashi T, Irino Y, Takenawa T, Miki H. Nucleoredoxin regulates glucose metabolism via phosphofructokinase 1. Biochem Biophys Res Commun 2013; 440:737-42. [PMID: 24120946 DOI: 10.1016/j.bbrc.2013.09.138] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 09/30/2013] [Indexed: 10/26/2022]
Abstract
Phosphofructokinase (PFK) 1 is a glycolytic enzyme, and its abnormality contributes to the development of multiple human diseases, such as cancer. Here, we report that nucleoredoxin (NRX), a thioredoxin-related oxidoreductase, is a novel interacting partner of PFK1. NRX binds directly to PFK1, and endogenous NRX and PFK1 interact in vivo. In NRX(-/-) mouse embryonic fibroblasts (MEFs), the oligomerization status of PFK1 is altered and the catalytic activity of PFK1 is decreased. NRX deficiency augmented levels of NADPH and reduced glutathione, two major cellular antioxidants generated through the pentose phosphate pathway. Indeed, NRX(-/-) MEFs are significantly more resistant to oxidative stress than NRX(+/+) MEFs. These results reveal a novel role of NRX in the regulation of PFK1 activity and in the balance between glycolysis and the pentose phosphate pathway.
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Affiliation(s)
- Yosuke Funato
- Department of Cellular Regulation, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan
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Mensonides FIC, Bakker BM, Cremazy F, Messiha HL, Mendes P, Boogerd FC, Westerhoff HV. A new regulatory principle for in vivo biochemistry: pleiotropic low affinity regulation by the adenine nucleotides--illustrated for the glycolytic enzymes of Saccharomyces cerevisiae. FEBS Lett 2013; 587:2860-7. [PMID: 23856461 DOI: 10.1016/j.febslet.2013.07.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 07/03/2013] [Indexed: 10/26/2022]
Abstract
Enzymology tends to focus on highly specific effects of substrates, allosteric modifiers, and products occurring at low concentrations, because these are most informative about the enzyme's catalytic mechanism. We hypothesized that at relatively high in vivo concentrations, important molecular monitors of the state of living cells, such as ATP, affect multiple enzymes of the former and that these interactions have gone unnoticed in enzymology. We test this hypothesis in terms of the effect that ATP, ADP, and AMP might have on the major free-energy delivering pathway of the yeast Saccharomyces cerevisiae. Assaying cell-free extracts, we collected a comprehensive set of quantitative kinetic data concerning the enzymes of the glycolytic and the ethanol fermentation pathways. We determined systematically the extent to which the enzyme activities depend on the concentrations of the adenine nucleotides. We found that the effects of the adenine nucleotides on enzymes catalysing reactions in which they are not directly involved as substrate or product, are substantial. This includes effects on the Michaelis-Menten constants, adding new perspective on these, 100 years after their introduction.
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Affiliation(s)
- Femke I C Mensonides
- Department of Molecular Cell Physiology, Faculty of Earth and Life Sciences, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
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Matsuoka Y, Shimizu K. Catabolite regulation analysis of Escherichia coli for acetate overflow mechanism and co-consumption of multiple sugars based on systems biology approach using computer simulation. J Biotechnol 2013; 168:155-73. [PMID: 23850830 DOI: 10.1016/j.jbiotec.2013.06.023] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 06/21/2013] [Accepted: 06/28/2013] [Indexed: 11/16/2022]
Abstract
It is quite important to understand the basic principle embedded in the main metabolism for the interpretation of the fermentation data. For this, it may be useful to understand the regulation mechanism based on systems biology approach. In the present study, we considered the perturbation analysis together with computer simulation based on the models which include the effects of global regulators on the pathway activation for the main metabolism of Escherichia coli. Main focus is the acetate overflow metabolism and the co-fermentation of multiple carbon sources. The perturbation analysis was first made to understand the nature of the feed-forward loop formed by the activation of Pyk by FDP (F1,6BP), and the feed-back loop formed by the inhibition of Pfk by PEP in the glycolysis. Those together with the effect of transcription factor Cra caused by FDP level affected the glycolysis activity. The PTS (phosphotransferase system) acts as the feed-back system by repressing the glucose uptake rate for the increase in the glucose uptake rate. It was also shown that the increased PTS flux (or glucose consumption rate) causes PEP/PYR ratio to be decreased, and EIIA-P, Cya, cAMP-Crp decreased, where cAMP-Crp in turn repressed TCA cycle and more acetate is formed. This was further verified by the detailed computer simulation. In the case of multiple carbon sources such as glucose and xylose, it was shown that the sequential utilization of carbon sources was observed for wild type, while the co-consumption of multiple carbon sources with slow consumption rates were observed for the ptsG mutant by computer simulation, and this was verified by experiments. Moreover, the effect of a specific gene knockout such as Δpyk on the metabolic characteristics was also investigated based on the computer simulation.
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Affiliation(s)
- Yu Matsuoka
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, Iizuka, Fukuoka 820-8502, Japan
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