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Hu X, Li C, Li Y, Jin Y, Wei L, Wang X, Xu Y, Hu Z. A Novel Glucose-6-Phosphate Isomerase Exists in Chicken Breast Meat: A Selenium-Containing Enzyme that Should Be Re-recognized Through New Eyes. Protein J 2023:10.1007/s10930-023-10105-9. [PMID: 36964419 DOI: 10.1007/s10930-023-10105-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2023] [Indexed: 03/26/2023]
Abstract
Glucose-6-phosphate isomerase (GPI) is a highly conserved glycolytic enzyme in nature, and less information was available for GPI from hens. In this study a newly discovered selenocysteine (Sec)-containing GPI in common chicken breast meat was first isolated, purified and identified. Data about LC-MS/MS, FTIR and Se species analyses show that the molecular weight of the enzyme is 62,091 Da and only one Sec is inserted at the 403rd position in the highly conserved primary domain SIS_PGI with sugar conversion function. The enzyme shows excellent activity against hydroxyl radicals as vitamin C (Vc) in vitro. It is deduced that the Sec-containing GPI in the chicken meat may depend on Sec in its molecular structure to resist reactive oxygen species (ROS) stress produced by the accompanying biochemical reactions in cells, to protect its stability and maintain its efficient function that catalyzes the conversion of glucose-6-phosphate to fructose-6-phosphate in the critical glycolytic pathway.
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Affiliation(s)
- Xin Hu
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
- Laboratory of Quality & Safety Risk Assessment for Agro-Products (Yangling), Ministry of Agriculture and Rural Affairs of the People's Republic of China, Yangling, 712100, Shaanxi, China
| | - Chenxi Li
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
- Laboratory of Quality & Safety Risk Assessment for Agro-Products (Yangling), Ministry of Agriculture and Rural Affairs of the People's Republic of China, Yangling, 712100, Shaanxi, China
| | - Yuancheng Li
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
- Laboratory of Quality & Safety Risk Assessment for Agro-Products (Yangling), Ministry of Agriculture and Rural Affairs of the People's Republic of China, Yangling, 712100, Shaanxi, China
| | - Yi Jin
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
- Laboratory of Quality & Safety Risk Assessment for Agro-Products (Yangling), Ministry of Agriculture and Rural Affairs of the People's Republic of China, Yangling, 712100, Shaanxi, China
| | - Lulu Wei
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
- Laboratory of Quality & Safety Risk Assessment for Agro-Products (Yangling), Ministry of Agriculture and Rural Affairs of the People's Republic of China, Yangling, 712100, Shaanxi, China
| | - Xinlei Wang
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
- Laboratory of Quality & Safety Risk Assessment for Agro-Products (Yangling), Ministry of Agriculture and Rural Affairs of the People's Republic of China, Yangling, 712100, Shaanxi, China
| | - Yanlong Xu
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China
- Laboratory of Quality & Safety Risk Assessment for Agro-Products (Yangling), Ministry of Agriculture and Rural Affairs of the People's Republic of China, Yangling, 712100, Shaanxi, China
| | - Zhongqiu Hu
- College of Food Science and Engineering, Northwest A&F University, Yangling, 712100, Shaanxi, China.
- Laboratory of Quality & Safety Risk Assessment for Agro-Products (Yangling), Ministry of Agriculture and Rural Affairs of the People's Republic of China, Yangling, 712100, Shaanxi, China.
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2
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Fernandez PL, Nagorski RW, Cristobal JR, Amyes TL, Richard JP. Phosphodianion Activation of Enzymes for Catalysis of Central Metabolic Reactions. J Am Chem Soc 2021; 143:2694-2698. [PMID: 33560827 PMCID: PMC7919737 DOI: 10.1021/jacs.0c13423] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
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The activation barriers ΔG⧧ for
kcat/Km for the reactions of
whole substrates catalyzed by 6-phosphogluconate dehydrogenase, glucose 6-phosphate
dehydrogenase, and glucose 6-phosphate isomerase are reduced by 11–13 kcal/mol by
interactions between the protein and the substrate phosphodianion. Between 4 and 6
kcal/mol of this dianion binding energy is expressed at the transition state for
phosphite dianion activation of the respective enzyme-catalyzed reactions of truncated
substrates d-xylonate or d-xylose. These and earlier results from
studies on β-phosphoglucomutase, triosephosphate isomerase, and glycerol
3-phosphate dehydrogenase define a cluster of six enzymes that catalyze reactions in
glycolysis or of glycolytic intermediates, and which utilize substrate dianion binding
energy for enzyme activation. Dianion-driven conformational changes, which convert
flexible open proteins to tight protein cages for the phosphorylated substrate, have
been thoroughly documented for five of these six enzymes. The clustering of metabolic
enzymes which couple phosphodianion-driven conformational changes to enzyme activation
suggests that this catalytic motif has been widely propagated in the proteome.
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Affiliation(s)
- Patrick L Fernandez
- Department of Chemistry, University at Buffalo, SUNY, Buffalo, New York 14260-3000, United States
| | - Richard W Nagorski
- Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160, United States
| | - Judith R Cristobal
- Department of Chemistry, University at Buffalo, SUNY, Buffalo, New York 14260-3000, United States
| | - Tina L Amyes
- Department of Chemistry, University at Buffalo, SUNY, Buffalo, New York 14260-3000, United States
| | - John P Richard
- Department of Chemistry, University at Buffalo, SUNY, Buffalo, New York 14260-3000, United States
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3
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Swope N, Lake KE, Barrow GH, Yu D, Fox DA, Columbus L. TM1385 from Thermotoga maritima functions as a phosphoglucose isomerase via cis-enediol-based mechanism with active site redundancy. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2021; 1869:140602. [PMID: 33422670 DOI: 10.1016/j.bbapap.2021.140602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 12/01/2020] [Accepted: 12/30/2020] [Indexed: 11/28/2022]
Abstract
Phosphoglucose isomerases (PGIs) belong to a class of enzymes that catalyze the reversible isomerization of glucose-6-phosphate to fructose-6-phosphate. PGIs are crucial in glycolysis and gluconeogenesis pathways and proposed as serving additional extracellular functions in eukaryotic organisms. The phosphoglucose isomerase function of TM1385, a previously uncharacterized protein from Thermotoga maritima, was hypothesized based on structural similarity to established PGI crystal structures and computational docking. Kinetic and colorimetric assays combined with 1H nuclear magnetic resonance (NMR) spectroscopy experimentally confirm that TM1385 is a phosphoglucose isomerase (TmPGI). Evidence of solvent exchange in 1H NMR spectra supports that TmPGI isomerization proceeds through a cis-enediol-based mechanism. To determine which amino acid residues are critical for TmPGI catalysis, putative active site residues were mutated with alanine and screened for activity. Results support that E281 is most important for TmPGI formation of the cis-enediol intermediate, and the presence of either H310 or K422 may be required for catalysis, similar to previous observations from homologous PGIs. However, only TmPGI E281A/Q415A and H310A/K422A double mutations abolished activity, suggesting that there are redundant catalytic residues, and Q415 may participate in sugar phosphate isomerization upon E281 mutation. Combined, we propose that TmPGI E281 participates directly in the cis-enediol intermediate step, and either H310 or K422 may facilitate sugar ring opening and closure.
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Affiliation(s)
- Nicole Swope
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | - Katherine E Lake
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | - Golda H Barrow
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | - Daniel Yu
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | - Daniel A Fox
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | - Linda Columbus
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA.
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4
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Zhang N, Meng X, Wu Y, Song H, Huang H, Wang F, Lv J. Highly Selective Isomerization of Glucose into Fructose Catalyzed by a Mimic Glucose Isomerase. ChemCatChem 2019. [DOI: 10.1002/cctc.201900143] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Ni Zhang
- Key Laboratory of Green Chemistry and Technology College of ChemistrySichuan University Chengdu 610064 P.R. China
| | - Xiang‐Guang Meng
- Key Laboratory of Green Chemistry and Technology College of ChemistrySichuan University Chengdu 610064 P.R. China
| | - Yan‐Yan Wu
- Key Laboratory of Green Chemistry and Technology College of ChemistrySichuan University Chengdu 610064 P.R. China
| | - Hong‐Jin Song
- Key Laboratory of Green Chemistry and Technology College of ChemistrySichuan University Chengdu 610064 P.R. China
| | - Hong Huang
- Key Laboratory of Green Chemistry and Technology College of ChemistrySichuan University Chengdu 610064 P.R. China
| | - Fei Wang
- Key Laboratory of Green Chemistry and Technology College of ChemistrySichuan University Chengdu 610064 P.R. China
| | - Jing Lv
- Key Laboratory of Green Chemistry and Technology College of ChemistrySichuan University Chengdu 610064 P.R. China
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5
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Brodkin HR, DeLateur NA, Somarowthu S, Mills CL, Novak WR, Beuning PJ, Ringe D, Ondrechen MJ. Prediction of distal residue participation in enzyme catalysis. Protein Sci 2015; 24:762-78. [PMID: 25627867 PMCID: PMC4420525 DOI: 10.1002/pro.2648] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Revised: 01/10/2015] [Accepted: 01/26/2015] [Indexed: 11/09/2022]
Abstract
A scoring method for the prediction of catalytically important residues in enzyme structures is presented and used to examine the participation of distal residues in enzyme catalysis. Scores are based on the Partial Order Optimum Likelihood (POOL) machine learning method, using computed electrostatic properties, surface geometric features, and information obtained from the phylogenetic tree as input features. Predictions of distal residue participation in catalysis are compared with experimental kinetics data from the literature on variants of the featured enzymes; some additional kinetics measurements are reported for variants of Pseudomonas putida nitrile hydratase (ppNH) and for Escherichia coli alkaline phosphatase (AP). The multilayer active sites of P. putida nitrile hydratase and of human phosphoglucose isomerase are predicted by the POOL log ZP scores, as is the single-layer active site of P. putida ketosteroid isomerase. The log ZP score cutoff utilized here results in over-prediction of distal residue involvement in E. coli alkaline phosphatase. While fewer experimental data points are available for P. putida mandelate racemase and for human carbonic anhydrase II, the POOL log ZP scores properly predict the previously reported participation of distal residues.
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Affiliation(s)
- Heather R Brodkin
- Department of Chemistry and Chemical Biology, Northeastern UniversityBoston, Massachusetts, 02115
- Department of Biochemistry, Rosenstiel Basic Medical Sciences Research Center, Brandeis UniversityWaltham, Massachusetts, 02454–9110
- Department of Chemistry, Rosenstiel Basic Medical Sciences Research Center, Brandeis UniversityWaltham, Massachusetts, 02454–9110
| | - Nicholas A DeLateur
- Department of Chemistry and Chemical Biology, Northeastern UniversityBoston, Massachusetts, 02115
| | - Srinivas Somarowthu
- Department of Chemistry and Chemical Biology, Northeastern UniversityBoston, Massachusetts, 02115
| | - Caitlyn L Mills
- Department of Chemistry and Chemical Biology, Northeastern UniversityBoston, Massachusetts, 02115
| | - Walter R Novak
- Department of Biochemistry, Rosenstiel Basic Medical Sciences Research Center, Brandeis UniversityWaltham, Massachusetts, 02454–9110
- Department of Chemistry, Rosenstiel Basic Medical Sciences Research Center, Brandeis UniversityWaltham, Massachusetts, 02454–9110
| | - Penny J Beuning
- Department of Chemistry and Chemical Biology, Northeastern UniversityBoston, Massachusetts, 02115
| | - Dagmar Ringe
- Department of Biochemistry, Rosenstiel Basic Medical Sciences Research Center, Brandeis UniversityWaltham, Massachusetts, 02454–9110
- Department of Chemistry, Rosenstiel Basic Medical Sciences Research Center, Brandeis UniversityWaltham, Massachusetts, 02454–9110
| | - Mary Jo Ondrechen
- Department of Chemistry and Chemical Biology, Northeastern UniversityBoston, Massachusetts, 02115
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6
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Haga A, Tanaka N, Funasaka T, Hashimoto K, Nakamura KT, Watanabe H, Raz A, Nagase H. The Autocrine Motility Factor (AMF) and AMF-receptor Combination Needs Sugar Chain Recognition Ability and Interaction Using the C-terminal Region of AMF. J Mol Biol 2006; 358:741-53. [PMID: 16563432 DOI: 10.1016/j.jmb.2006.02.046] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2005] [Revised: 02/14/2006] [Accepted: 02/16/2006] [Indexed: 11/21/2022]
Abstract
The autocrine motility factor (AMF) promotes cellular locomotion or invasion, and regulates tumor angiogenesis or ascites accumulation. These signals are triggered by binding between AMF and its receptor (AMFR), a glycoprotein on the cell surface. AMF has been identified as phosphohexose isomerase (PHI). Previous reports have suggested that the substrate-recognition of exo-PHI is significant for receptor binding. Crystallographic studies have shown that AMF consists of three domains, and that the substrate or inhibitor of PHI is stored between the large and small domains, corresponding to approximately residues 117-288. Here, site-directed mutagenesis was used to investigate 18 recombinant human AMF point mutants involving critical amino acid residues for substrate or enzyme inhibitor recognition or binding. Mutation of residues that interact with the phosphate group of the PHI substrate significantly reduced the cell motility-stimulating activity. Their binding capacities for AMFR were also lower than wild-type human AMF. Mutants that retained the enzymic activity showed the motility-stimulating effect and receptor binding and had sensitivity to a PHI inhibitor. Mutant AMFR lacking the N-sugar chain was expressed on the cell membrane but did not respond to AMF-stimulation, and N-glycosidase-treated AMFR did not compete with receptor binding of AMF. Furthermore, the AMF domains that contain the substrate storage domain and C-terminal region stimulate cell locomotion. These results suggest that the N-glyco side-chain of AMFR is a trigger and that interaction between the 117-C-terminal part of AMF and the extracellular core protein of AMFR is needed during AMF-AMFR interactions.
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Affiliation(s)
- Arayo Haga
- Gifu Pharmaceutical University, 5-6-1 Mitahora-Higashi, Gifu 502-8585, Japan.
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7
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Mathur D, Ahsan Z, Tiwari M, Garg LC. Biochemical characterization of recombinant phosphoglucose isomerase of Mycobacterium tuberculosis. Biochem Biophys Res Commun 2005; 337:626-32. [PMID: 16212940 DOI: 10.1016/j.bbrc.2005.09.092] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2005] [Accepted: 09/15/2005] [Indexed: 10/25/2022]
Abstract
Phosphoglucose isomerase (PGI) is a well-characterized ubiquitous enzyme involved in the glycolytic pathway. It catalyzes the reversible isomerization of D-glucopyranose-6-phosphate and D-fructofuranose-6-phosphate and is present in all living cells. However, there is interspecies variation at the level of the primary structure which sometimes produces heterogeneity at the structural and functional levels. In order to evaluate and characterize the mycobacterial PGI, the gene encoding the PGI from Mycobacterium tuberculosis H37Rv was cloned in pET-22b(+) vector and expressed in Escherichia coli. The target DNA was PCR amplified from the bacterial artificial chromosome using specific primers and cloned under the control of T7 promoter. Upon induction with IPTG, the recombinant PGI (rPGI) expressed partly as soluble protein and partly as inclusion bodies. The rPGI from the soluble fraction was purified to near homogeneity by ion-exchange chromatography. Mass spectrum analysis of the purified rPGI revealed its mass to be 61.45 kDa. The purified rPGI was enzymatically active and the specific activity was 600 U/mg protein. The K(m) of rPGI was determined to be 0.318 mM for fructose-6-phosphate and the K(i) was 0.8 mM for 6-phosphogluconate. The rPGI exhibited optimal activity at 37 degrees C and pH 9.0, and did not require mono- or divalent cations for its activity.
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Affiliation(s)
- Divya Mathur
- Gene Regulation Laboratory, National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, India
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8
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Solomons JTG, Zimmerly EM, Burns S, Krishnamurthy N, Swan MK, Krings S, Muirhead H, Chirgwin J, Davies C. The Crystal Structure of Mouse Phosphoglucose Isomerase at 1.6Å Resolution and its Complex with Glucose 6-Phosphate Reveals the Catalytic Mechanism of Sugar Ring Opening. J Mol Biol 2004; 342:847-60. [PMID: 15342241 DOI: 10.1016/j.jmb.2004.07.085] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2004] [Revised: 07/19/2004] [Accepted: 07/23/2004] [Indexed: 11/21/2022]
Abstract
Phosphoglucose isomerase (PGI) is an enzyme of glycolysis that interconverts glucose 6-phosphate (G6P) and fructose 6-phosphate (F6P) but, outside the cell, is a multifunctional cytokine. High-resolution crystal structures of the enzyme from mouse have been determined in native form and in complex with the inhibitor erythrose 4-phosphate, and with the substrate glucose 6-phosphate. In the substrate-bound structure, the glucose sugar is observed in both straight-chain and ring forms. This structure supports a specific role for Lys518 in enzyme-catalyzed ring opening and we present a "push-pull" mechanism in which His388 breaks the O5-C1 bond by donating a proton to the ring oxygen atom and, simultaneously, Lys518 abstracts a proton from the C1 hydroxyl group. The reverse occurs in ring closure. The transition from ring form to straight-chain substrate is achieved through rotation of the C3-C4 bond, which brings the C1-C2 region into close proximity to Glu357, the base catalyst for the isomerization step. The structure with G6P also explains the specificity of PGI for glucose 6-phosphate over mannose 6-isomerase (M6P). To isomerize M6P to F6P requires a rotation of its C2-C3 bond but in PGI this is sterically blocked by Gln511.
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Affiliation(s)
- J T Graham Solomons
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA
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9
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Kuper J, Winking J, Hecht HJ, Mendel RR, Schwarz G. The active site of the molybdenum cofactor biosynthetic protein domain Cnx1G. Arch Biochem Biophys 2003; 411:36-46. [PMID: 12590921 DOI: 10.1016/s0003-9861(02)00714-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The final step of molybdenum cofactor biosynthesis in plants is catalyzed by the two-domain protein Cnx1. The G domain of Cnx1 (Cnx1G) binds molybdopterin with high affinity and transfers molybdenum to molybdopterin. Here, we describe the functional and structural characterization of structure-based Cnx1G mutants. For molybdopterin binding residues Thr542 and Ser573 were found to be important because different mutations of those residues resulted in 7- to 26-fold higher k(D) values for molybdopterin binding. Furthermore, we showed that the terminal phosphate of molybdopterin is directly involved in protein-pterin interactions as dephosphorylated molybdopterin binds with one magnitude of order lower affinity to the wild-type protein. Molybdopterin binding was not affected in mutants defective in Ser476, Asp486, or Asp515. However, molybdenum insertion was completely abolished, indicating their important role for catalysis. Based on these results we propose the binding of molybdopterin to a large depression in the structure of Cnx1G formed by beta5, alpha5, beta6, and alpha6, whereas the negatively charged depression formed by the loop between beta3 and alpha4, the N-terminal end of alpha2, the 3(10) helix, and the region between beta6 and alpha6 is involved in catalysis.
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Affiliation(s)
- Jochen Kuper
- Department of Plant Biology, Technical University of Braunschweig, 38028, Braunschweig, Germany
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10
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Tanaka N, Haga A, Uemura H, Akiyama H, Funasaka T, Nagase H, Raz A, Nakamura KT. Inhibition mechanism of cytokine activity of human autocrine motility factor examined by crystal structure analyses and site-directed mutagenesis studies. J Mol Biol 2002; 318:985-97. [PMID: 12054796 DOI: 10.1016/s0022-2836(02)00186-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Autocrine motility factor (AMF), a tumor-secreted cytokine, stimulates cell migration in vitro and metastasis in vivo. AMF is genetically identical with the extracellular cytokines neuroleukin (NLK) and maturation factor (MF) and, interestingly, the intracellular enzyme phosphohexose isomerase (PHI). The crystal structures of the inhibitor-free open form and the inhibitor (erythrose 4-phosphate, E4P, a strong inhibitor of AMF's cytokine activity)-bound closed form of human AMF have been determined at 1.9 A and 2.4 A resolution, respectively. Upon E4P binding, local conformation changes (open to closed) occur around the inhibitor-binding site. The E4P-bound structure shows that the location of the inhibitor (of cytokine activity) binding site of human AMF is very similar to those of the inhibitor (of enzymatic activity) binding sites of PHIs. The present study shows clearly that there is structural overlap of the regions responsible for the enzymatic and cytokine functions of AMF and PHI and suggests two scenarios for the inhibition mechanism of cytokine activity of AMF by the carbohydrate phosphate group. One likely scenario is that the compound could compete for AMF binding with the carbohydrate moiety of the AMF receptor (AMFR), which is a glycosylated seven-transmembrane helix protein. The other scenario is that the local conformation changes upon inhibitor binding may affect the AMF-AMFR interactions. To examine roles of the residues in the inhibitor-binding site, two mutant AMFs were prepared. Replacements of His389, which is hydrogen-bonded to the hydroxyl group of E4P by Phe, and Thr215, which is hydrogen-bonded to the phosphate group of E4P by Asp, result in mutant AMFs that are impaired in cytokine activity. These results suggest a role for these amino acids in recognition of a carbohydrate moiety of the AMFR. Since the E4P is one of the smallest compounds having AMF inhibitor activity, knowledge of the present crystal structure would provide an insight into the lead compound design of more effective AMF inhibitors.
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Affiliation(s)
- Nobutada Tanaka
- School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
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11
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Arsenieva D, Hardre R, Salmon L, Jeffery CJ. The crystal structure of rabbit phosphoglucose isomerase complexed with 5-phospho-D-arabinonohydroxamic acid. Proc Natl Acad Sci U S A 2002; 99:5872-7. [PMID: 11983887 PMCID: PMC122869 DOI: 10.1073/pnas.052131799] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2001] [Accepted: 03/06/2002] [Indexed: 11/18/2022] Open
Abstract
Phosphoglucose isomerase (EC ) catalyzes the second step in glycolysis, the reversible isomerization of D-glucose 6-phosphate to D-fructose 6-phosphate. The reaction mechanism involves acid-base catalysis with proton transfer and proceeds through a cis-enediol(ate) intermediate. 5-Phospho-D-arabinonohydroxamic acid (5PAH) is a synthetic small molecule that resembles the reaction intermediate, differing only in that it has a nitrogen atom in place of C1. Hence, 5PAH is the best inhibitor of the isomerization reaction reported to date with a K(i) of 2 x 10(-7) M. Here we report the crystal structure of rabbit phosphoglucose isomerase complexed with 5PAH at 1.9 A resolution. The interaction of 5PAH with amino acid residues in the enzyme active site supports a model of the catalytic mechanism in which Glu-357 transfers a proton between C1 and C2 and Arg-272 helps stabilize the intermediate. It also suggests a mechanism for proton transfer between O1 and O2.
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Affiliation(s)
- Diana Arsenieva
- Laboratory for Molecular Biology, MC567, Department of Biological Sciences, University of Illinois, Chicago, IL 60607, USA
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