1
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Cruz-Navarrete FA, Baxter NJ, Flinders AJ, Buzoianu A, Cliff MJ, Baker PJ, Waltho JP. Peri active site catalysis of proline isomerisation is the molecular basis of allomorphy in β-phosphoglucomutase. Commun Biol 2024; 7:909. [PMID: 39068257 PMCID: PMC11283535 DOI: 10.1038/s42003-024-06577-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Accepted: 07/11/2024] [Indexed: 07/30/2024] Open
Abstract
Metabolic regulation occurs through precise control of enzyme activity. Allomorphy is a post-translational fine control mechanism where the catalytic rate is governed by a conformational switch that shifts the enzyme population between forms with different activities. β-Phosphoglucomutase (βPGM) uses allomorphy in the catalysis of isomerisation of β-glucose 1-phosphate to glucose 6-phosphate via β-glucose 1,6-bisphosphate. Herein, we describe structural and biophysical approaches to reveal its allomorphic regulatory mechanism. Binding of the full allomorphic activator β-glucose 1,6-bisphosphate stimulates enzyme closure, progressing through NAC I and NAC III conformers. Prior to phosphoryl transfer, loops positioned on the cap and core domains are brought into close proximity, modulating the environment of a key proline residue. Hence accelerated isomerisation, likely via a twisted anti/C4-endo transition state, leads to the rapid predominance of active cis-P βPGM. In contrast, binding of the partial allomorphic activator fructose 1,6-bisphosphate arrests βPGM at a NAC I conformation and phosphoryl transfer to both cis-P βPGM and trans-P βPGM occurs slowly. Thus, allomorphy allows a rapid response to changes in food supply while not otherwise impacting substantially on levels of important metabolites.
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Affiliation(s)
- F Aaron Cruz-Navarrete
- School of Biosciences, University of Sheffield, Sheffield, S10 2TN, UK
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, 38105, USA
| | - Nicola J Baxter
- School of Biosciences, University of Sheffield, Sheffield, S10 2TN, UK
- Manchester Institute of Biotechnology and Department of Chemistry, The University of Manchester, Manchester, M1 7DN, UK
| | - Adam J Flinders
- School of Biosciences, University of Sheffield, Sheffield, S10 2TN, UK
- Cancer Research UK, Manchester Institute, Patterson Building, Manchester, M20 4BX, UK
| | - Anamaria Buzoianu
- School of Biosciences, University of Sheffield, Sheffield, S10 2TN, UK
- Department of Chemistry, Biochemistry and Pharmacy, University of Bern, Bern, 3012, Switzerland
| | - Matthew J Cliff
- Manchester Institute of Biotechnology and Department of Chemistry, The University of Manchester, Manchester, M1 7DN, UK
| | - Patrick J Baker
- School of Biosciences, University of Sheffield, Sheffield, S10 2TN, UK
| | - Jonathan P Waltho
- School of Biosciences, University of Sheffield, Sheffield, S10 2TN, UK.
- Manchester Institute of Biotechnology and Department of Chemistry, The University of Manchester, Manchester, M1 7DN, UK.
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2
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Sato S, Fan PH, Yeh YC, Liu HW. Complete In Vitro Reconstitution of the Apramycin Biosynthetic Pathway Demonstrates the Unusual Incorporation of a β-d-Sugar Nucleotide in the Final Glycosylation Step. J Am Chem Soc 2024; 146:10103-10114. [PMID: 38546392 PMCID: PMC11317085 DOI: 10.1021/jacs.4c01233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Apramycin is a widely used aminoglycoside antibiotic with applications in veterinary medicine. It is composed of a 4-amino-4-deoxy-d-glucose moiety and the pseudodisaccharide aprosamine, which is an adduct of 2-deoxystreptamine and an unusual eight-carbon bicyclic dialdose. Despite its extensive study and relevance to medical practice, the biosynthetic pathway of this complex aminoglycoside nevertheless remains incomplete. Herein, the remaining unknown steps of apramycin biosynthesis are reconstituted in vitro, thereby leading to a comprehensive picture of its biological assembly. In particular, phosphomutase AprJ and nucleotide transferase AprK are found to catalyze the conversion of glucose 6-phosphate to NDP-β-d-glucose as a critical biosynthetic intermediate. Moreover, the dehydrogenase AprD5 and transaminase AprL are identified as modifying this intermediate via introduction of an amino group at the 4″ position without requiring prior 6″-deoxygenation as is typically encountered in aminosugar biosynthesis. Finally, the glycoside hydrolase family 65 protein AprO is shown to utilize NDP-β-d-glucose or NDP-4"-amino-4"-deoxy-β-d-glucose to form the 8',1″-O-glycosidic linkage of saccharocin or apramycin, respectively. As the activated sugar nucleotides in all known natural glycosylation reactions involve either NDP-α-d-hexoses or NDP-β-l-hexoses, the reported chemistry expands the scope of known biological glycosylation reactions to NDP-β-d-hexoses, with important implications for the understanding and repurposing of aminoglycoside biosynthesis.
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3
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Pfeiffer M, Crean RM, Moreira C, Parracino A, Oberdorfer G, Brecker L, Hammerschmidt F, Kamerlin SCL, Nidetzky B. Essential Functional Interplay of the Catalytic Groups in Acid Phosphatase. ACS Catal 2022; 12:3357-3370. [PMID: 35356705 PMCID: PMC8938923 DOI: 10.1021/acscatal.1c05656] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/31/2022] [Indexed: 01/15/2023]
Abstract
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The cooperative interplay
between the functional devices of a preorganized
active site is fundamental to enzyme catalysis. An in-depth understanding
of this phenomenon is central to elucidating the remarkable efficiency
of natural enzymes and provides an essential benchmark for enzyme
design and engineering. Here, we study the functional interconnectedness
of the catalytic nucleophile (His18) in an acid phosphatase by analyzing
the consequences of its replacement with aspartate. We present crystallographic,
biochemical, and computational evidence for a conserved mechanistic
pathway via a phospho-enzyme intermediate on Asp18. Linear free-energy
relationships for phosphoryl transfer from phosphomonoester substrates
to His18/Asp18 provide evidence for the cooperative interplay between
the nucleophilic and general-acid catalytic groups in the wild-type
enzyme, and its substantial loss in the H18D variant. As an isolated
factor of phosphatase efficiency, the advantage of a histidine compared
to an aspartate nucleophile is ∼104-fold. Cooperativity
with the catalytic acid adds ≥102-fold to that advantage.
Empirical valence bond simulations of phosphoryl transfer from glucose
1-phosphate to His and Asp in the enzyme explain the loss of activity
of the Asp18 enzyme through a combination of impaired substrate positioning
in the Michaelis complex, as well as a shift from early to late protonation
of the leaving group in the H18D variant. The evidence presented furthermore
suggests that the cooperative nature of catalysis distinguishes the
enzymatic reaction from the corresponding reaction in solution and
is enabled by the electrostatic preorganization of the active site.
Our results reveal sophisticated discrimination in multifunctional
catalysis of a highly proficient phosphatase active site.
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Affiliation(s)
- Martin Pfeiffer
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Petersgasse 12/I, 8010 Graz, Austria.,Austrian Centre of Industrial Biotechnology, Petersgasse 14, 8010 Graz, Austria
| | - Rory M Crean
- Department of Chemistry-BMC, Uppsala University, BMC Box 576, S-751 23 Uppsala, Sweden
| | - Catia Moreira
- Department of Chemistry-BMC, Uppsala University, BMC Box 576, S-751 23 Uppsala, Sweden
| | - Antonietta Parracino
- Department of Chemistry-BMC, Uppsala University, BMC Box 576, S-751 23 Uppsala, Sweden
| | - Gustav Oberdorfer
- Institute of Biochemistry, Graz University of Technology, NAWI Graz, Petersgasse 12/II, 8010 Graz, Austria
| | - Lothar Brecker
- Department of Organic Chemistry, University of Vienna, Währingerstraße 38, 1090 Vienna, Austria
| | - Friedrich Hammerschmidt
- Department of Organic Chemistry, University of Vienna, Währingerstraße 38, 1090 Vienna, Austria
| | | | - Bernd Nidetzky
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Petersgasse 12/I, 8010 Graz, Austria.,Austrian Centre of Industrial Biotechnology, Petersgasse 14, 8010 Graz, Austria
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4
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Robertson AJ, Cruz-Navarrete FA, Wood HP, Vekaria N, Hounslow AM, Bisson C, Cliff MJ, Baxter NJ, Waltho JP. An Enzyme with High Catalytic Proficiency Utilizes Distal Site Substrate Binding Energy to Stabilize the Closed State but at the Expense of Substrate Inhibition. ACS Catal 2022; 12:3149-3164. [PMID: 35692864 PMCID: PMC9171722 DOI: 10.1021/acscatal.1c05524] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 02/10/2022] [Indexed: 02/05/2023]
Abstract
Understanding the factors that underpin the enormous catalytic proficiencies of enzymes is fundamental to catalysis and enzyme design. Enzymes are, in part, able to achieve high catalytic proficiencies by utilizing the binding energy derived from nonreacting portions of the substrate. In particular, enzymes with substrates containing a nonreacting phosphodianion group coordinated in a distal site have been suggested to exploit this binding energy primarily to facilitate a conformational change from an open inactive form to a closed active form, rather than to either induce ground state destabilization or stabilize the transition state. However, detailed structural evidence for the model is limited. Here, we use β-phosphoglucomutase (βPGM) to investigate the relationship between binding a phosphodianion group in a distal site, the adoption of a closed enzyme form, and catalytic proficiency. βPGM catalyzes the isomerization of β-glucose 1-phosphate to glucose 6-phosphate via phosphoryl transfer reactions in the proximal site, while coordinating a phosphodianion group of the substrate(s) in a distal site. βPGM has one of the largest catalytic proficiencies measured and undergoes significant domain closure during its catalytic cycle. We find that side chain substitution at the distal site results in decreased substrate binding that destabilizes the closed active form but is not sufficient to preclude the adoption of a fully closed, near-transition state conformation. Furthermore, we reveal that binding of a phosphodianion group in the distal site stimulates domain closure even in the absence of a transferring phosphoryl group in the proximal site, explaining the previously reported β-glucose 1-phosphate inhibition. Finally, our results support a trend whereby enzymes with high catalytic proficiencies involving phosphorylated substrates exhibit a greater requirement to stabilize the closed active form.
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Affiliation(s)
- Angus J. Robertson
- School of Biosciences, The University of Sheffield, Sheffield, S10 2TN, United Kingdom
| | | | - Henry P. Wood
- School of Biosciences, The University of Sheffield, Sheffield, S10 2TN, United Kingdom
| | - Nikita Vekaria
- Manchester Institute of Biotechnology and Department of Chemistry, The University of Manchester, Manchester, M1 7DN, United Kingdom
| | - Andrea M. Hounslow
- School of Biosciences, The University of Sheffield, Sheffield, S10 2TN, United Kingdom
| | - Claudine Bisson
- School of Biosciences, The University of Sheffield, Sheffield, S10 2TN, United Kingdom
| | - Matthew J. Cliff
- Manchester Institute of Biotechnology and Department of Chemistry, The University of Manchester, Manchester, M1 7DN, United Kingdom
| | - Nicola J. Baxter
- School of Biosciences, The University of Sheffield, Sheffield, S10 2TN, United Kingdom
- Manchester Institute of Biotechnology and Department of Chemistry, The University of Manchester, Manchester, M1 7DN, United Kingdom
| | - Jonathan P. Waltho
- School of Biosciences, The University of Sheffield, Sheffield, S10 2TN, United Kingdom
- Manchester Institute of Biotechnology and Department of Chemistry, The University of Manchester, Manchester, M1 7DN, United Kingdom
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5
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Robertson AJ, Wilson AL, Burn MJ, Cliff MJ, Popelier PLA, Waltho JP. The Relationship between Enzyme Conformational Change, Proton Transfer, and Phosphoryl Transfer in β-Phosphoglucomutase. ACS Catal 2021. [DOI: 10.1021/acscatal.1c01389] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Angus J. Robertson
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Alex L. Wilson
- Department of Chemistry, Manchester Institute of Biotechnology, The University of Manchester, Manchester M1 7DN, United Kingdom
| | - Matthew J. Burn
- Department of Chemistry, Manchester Institute of Biotechnology, The University of Manchester, Manchester M1 7DN, United Kingdom
| | - Matthew J. Cliff
- Department of Chemistry, Manchester Institute of Biotechnology, The University of Manchester, Manchester M1 7DN, United Kingdom
| | - Paul L. A. Popelier
- Department of Chemistry, Manchester Institute of Biotechnology, The University of Manchester, Manchester M1 7DN, United Kingdom
| | - Jonathan P. Waltho
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Sheffield S10 2TN, United Kingdom
- Department of Chemistry, Manchester Institute of Biotechnology, The University of Manchester, Manchester M1 7DN, United Kingdom
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6
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Allomorphy as a mechanism of post-translational control of enzyme activity. Nat Commun 2020; 11:5538. [PMID: 33139716 PMCID: PMC7608592 DOI: 10.1038/s41467-020-19215-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 09/23/2020] [Indexed: 11/08/2022] Open
Abstract
Enzyme regulation is vital for metabolic adaptability in living systems. Fine control of enzyme activity is often delivered through post-translational mechanisms, such as allostery or allokairy. β-phosphoglucomutase (βPGM) from Lactococcus lactis is a phosphoryl transfer enzyme required for complete catabolism of trehalose and maltose, through the isomerisation of β-glucose 1-phosphate to glucose 6-phosphate via β-glucose 1,6-bisphosphate. Surprisingly for a gatekeeper of glycolysis, no fine control mechanism of βPGM has yet been reported. Herein, we describe allomorphy, a post-translational control mechanism of enzyme activity. In βPGM, isomerisation of the K145-P146 peptide bond results in the population of two conformers that have different activities owing to repositioning of the K145 sidechain. In vivo phosphorylating agents, such as fructose 1,6-bisphosphate, generate phosphorylated forms of both conformers, leading to a lag phase in activity until the more active phosphorylated conformer dominates. In contrast, the reaction intermediate β-glucose 1,6-bisphosphate, whose concentration depends on the β-glucose 1-phosphate concentration, couples the conformational switch and the phosphorylation step, resulting in the rapid generation of the more active phosphorylated conformer. In enabling different behaviours for different allomorphic activators, allomorphy allows an organism to maximise its responsiveness to environmental changes while minimising the diversion of valuable metabolites. β-phosphoglucomutase (βPGM) from Lactococcus lactis is a phosphoryl transfer enzyme required for catabolism of trehalose and maltose. Coupled analyses of multiple βPGM structures and enzymatic activity lead to the proposal of allomorphy — a post-translational mechanism controlling enzyme activity.
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7
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Harvey CM, O'Toole KH, Liu C, Mariano P, Dunaway-Mariano D, Allen KN. Structural Analysis of Binding Determinants of Salmonella typhimurium Trehalose-6-phosphate Phosphatase Using Ground-State Complexes. Biochemistry 2020; 59:3247-3257. [PMID: 32786412 DOI: 10.1021/acs.biochem.0c00317] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Trehalose-6-phosphate phosphatase (T6PP) catalyzes the dephosphorylation of trehalose 6-phosphate (T6P) to the disaccharide trehalose. The enzyme is not present in mammals but is essential to the viability of multiple lower organisms as trehalose is a critical metabolite, and T6P accumulation is toxic. Hence, T6PP is a target for therapeutics of human pathologies caused by bacteria, fungi, and parasitic nematodes. Here, we report the X-ray crystal structures of Salmonella typhimurium T6PP (StT6PP) in its apo form and in complex with the cofactor Mg2+ and the substrate analogue trehalose 6-sulfate (T6S), the product trehalose, or the competitive inhibitor 4-n-octylphenyl α-d-glucopyranoside 6-sulfate (OGS). OGS replaces the substrate phosphoryl group with a sulfate group and the glucosyl ring distal to the sulfate group with an octylphenyl moiety. The structures of these substrate-analogue and product complexes with T6PP show that specificity is conferred via hydrogen bonds to the glucosyl group proximal to the phosphoryl moiety through Glu123, Lys125, and Glu167, conserved in T6PPs from multiple species. The structure of the first-generation inhibitor OGS shows that it retains the substrate-binding interactions observed for the sulfate group and the proximal glucosyl ring. The OGS octylphenyl moiety binds in a unique manner, indicating that this subsite can tolerate various chemotypes. Together, these findings show that these conserved interactions at the proximal glucosyl ring binding site could provide the basis for the development of broad-spectrum therapeutics, whereas variable interactions at the divergent distal subsite could present an opportunity for the design of potent organism-specific therapeutics.
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Affiliation(s)
- Christine M Harvey
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States
| | - Katherine H O'Toole
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States
| | - Chunliang Liu
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Patrick Mariano
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Debra Dunaway-Mariano
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Karen N Allen
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States
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8
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Cruz-Navarrete FA, Baxter NJ, Wood HP, Hounslow AM, Waltho JP. 1H, 15N and 13C backbone resonance assignments of the P146A variant of β-phosphoglucomutase from Lactococcus lactis in its substrate-free form. BIOMOLECULAR NMR ASSIGNMENTS 2019; 13:349-356. [PMID: 31396843 PMCID: PMC6713671 DOI: 10.1007/s12104-019-09904-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 07/20/2019] [Indexed: 06/10/2023]
Abstract
β-Phosphoglucomutase (βPGM) is a magnesium-dependent phosphoryl transfer enzyme that catalyses the reversible isomerisation of β-glucose 1-phosphate and glucose 6-phosphate, via two phosphoryl transfer steps and a β-glucose 1,6-bisphosphate intermediate. Substrate-free βPGM is an essential component of the catalytic cycle and an understanding of its dynamics would present significant insights into βPGM functionality, and enzyme catalysed phosphoryl transfer in general. Previously, 30 residues around the active site of substrate-free βPGMWT were identified as undergoing extensive millisecond dynamics and were unassignable. Here we report 1H, 15N and 13C backbone resonance assignments of the P146A variant (βPGMP146A) in its substrate-free form, where the K145-A146 peptide bond adopts a trans conformation in contrast to all crystal structures of βPGMWT, where the K145-P146 peptide bond is cis. In βPGMP146A millisecond dynamics are suppressed for all but 17 residues, allowing 92% of backbone resonances to be assigned. Secondary structure predictions using TALOS-N reflect βPGM crystal structures, and a chemical shift comparison between substrate-free βPGMP146A and βPGMWT confirms that the solution conformations are very similar, except for the D137-A147 loop. Hence, the isomerisation state of the 145-146 peptide bond has little effect on structure but the cis conformation triggers millisecond dynamics in the hinge (V12-T16), the nucleophile (D8) and residues that coordinate the transferring phosphate group (D8 and S114-S116), and the D137-A147 loop (V141-A142 and K145). These millisecond dynamics occur in addition to those for residues involved in coordinating the catalytic MgII ion and the L44-L53 loop responsible for substrate discrimination.
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Affiliation(s)
- F Aaron Cruz-Navarrete
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
| | - Nicola J Baxter
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Henry P Wood
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
| | - Andrea M Hounslow
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
| | - Jonathan P Waltho
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK.
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
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9
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Monticelli M, Liguori L, Allocca M, Andreotti G, Cubellis MV. β-Glucose-1,6-Bisphosphate Stabilizes Pathological Phophomannomutase2 Mutants In Vitro and Represents a Lead Compound to Develop Pharmacological Chaperones for the Most Common Disorder of Glycosylation, PMM2-CDG. Int J Mol Sci 2019; 20:E4164. [PMID: 31454904 PMCID: PMC6747070 DOI: 10.3390/ijms20174164] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 08/13/2019] [Accepted: 08/22/2019] [Indexed: 12/13/2022] Open
Abstract
A large number of mutations causing PMM2-CDG, which is the most frequent disorder of glycosylation, destabilize phosphomannomutase2. We looked for a pharmacological chaperone to cure PMM2-CDG, starting from the structure of a natural ligand of phosphomannomutase2, α-glucose-1,6-bisphosphate. The compound, β-glucose-1,6-bisphosphate, was synthesized and characterized via 31P-NMR. β-glucose-1,6-bisphosphate binds its target enzyme in silico. The binding induces a large conformational change that was predicted by the program PELE and validated in vitro by limited proteolysis. The ability of the compound to stabilize wild type phosphomannomutase2, as well as frequently encountered pathogenic mutants, was measured using thermal shift assay. β-glucose-1,6-bisphosphate is relatively resistant to the enzyme that specifically hydrolyses natural esose-bisphosphates.
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Affiliation(s)
- Maria Monticelli
- Dipartimento di Biologia, Università Federico II, 80126 Napoli, Italy
| | - Ludovica Liguori
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania "Luigi Vanvitelli", 81100 Caserta, Italy
- Istituto di Chimica Biomolecolare-CNR, 80078 Pozzuoli, Italy
| | - Mariateresa Allocca
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania "Luigi Vanvitelli", 81100 Caserta, Italy
- Istituto di Chimica Biomolecolare-CNR, 80078 Pozzuoli, Italy
| | | | - Maria Vittoria Cubellis
- Dipartimento di Biologia, Università Federico II, 80126 Napoli, Italy
- Istituto di Chimica Biomolecolare-CNR, 80078 Pozzuoli, Italy
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10
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Karan S, Pratap B, Yadav SPS, Ashish, Saxena AK. Low-resolution SAXS and structural dynamics analysis on M. tuberculosis GmhB enzyme involved in GDP-heptose biosynthetic pathway. Int J Biol Macromol 2019; 136:676-685. [PMID: 31207333 DOI: 10.1016/j.ijbiomac.2019.06.035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 06/05/2019] [Accepted: 06/05/2019] [Indexed: 01/13/2023]
Abstract
The M. tuberculosis GmhB protein converts the d-glycero-α-d-manno-heptose 1,7-bisphosphate (GMB) intermediate into d-glycero-α-d-manno-heptose 1-phosphate by removing the phosphate group at the C-7 position. To understand the structure and substrate binding mechanism, the MtbGmhB was purified which elutes as monomer on gel filtration column. The small angle x-ray scattering analysis shows that MtbGmhB forms fully folded monomer with shape profile similar to its modeled structure. The circular dichroism analysis shows 38% α-helix, 15% β-sheets and 47% random coil structures in MtbGmhB, similar to haloalkanoic acid dehalogenase (HAD) phosphohydrolase enzymes. The modeled MtbGmhB structure shows the catalytic site, which forms a concave, semicircular surface using the three loops around GMB substrate binding site. Dynamic simulation analysis on (i) Apo (ii) GMB bound (iii) GMB + Mg2+ bound (iv) Zn2+ +GMB + Mg2+ bound MtbGmhB structures show that Zn2+ as well as Mg2+ ions stabilize the loop conformation and trigger the changes in GMB substrate binding to active site of MtbGmhB. Upon demetallization, the large conformational changes occurred in ions binding loops, and leads to difference in GMB substrate binding to MtbGmhB. Our study provides information about structure and substrate binding of MtbGmhB, which may contribute in therapeutic development against M. tuberculosis.
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Affiliation(s)
- Sumita Karan
- Rm-403/440, Structural Biology Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi-67, India
| | - Bhanu Pratap
- Rm-403/440, Structural Biology Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi-67, India
| | - Shiv Pratap S Yadav
- Protein Science and Engineering Division, Institute of Microbial Technology, Sector 39-A, Chandigarh-160036, India
| | - Ashish
- Protein Science and Engineering Division, Institute of Microbial Technology, Sector 39-A, Chandigarh-160036, India
| | - Ajay K Saxena
- Rm-403/440, Structural Biology Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi-67, India.
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11
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Krishnan A, Burroughs AM, Iyer LM, Aravind L. Unexpected Evolution of Lesion-Recognition Modules in Eukaryotic NER and Kinetoplast DNA Dynamics Proteins from Bacterial Mobile Elements. iScience 2018; 9:192-208. [PMID: 30396152 PMCID: PMC6222260 DOI: 10.1016/j.isci.2018.10.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 10/15/2018] [Accepted: 10/15/2018] [Indexed: 12/29/2022] Open
Abstract
The provenance of several components of major uniquely eukaryotic molecular machines are increasingly being traced back to prokaryotic biological conflict systems. Here, we demonstrate that the N-terminal single-stranded DNA-binding domain from the anti-restriction protein ArdC, deployed by bacterial mobile elements against their host, was independently acquired twice by eukaryotes, giving rise to the DNA-binding domains of XPC/Rad4 and the Tc-38-like proteins in the stem kinetoplastid. In both instances, the ArdC-N domain tandemly duplicated forming an extensive DNA-binding interface. In XPC/Rad4, the ArdC-N domains (BHDs) also fused to the inactive transglutaminase domain of a peptide-N-glycanase ultimately derived from an archaeal conflict system. Alongside, we delineate several parallel acquisitions from conjugative elements/bacteriophages that gave rise to key components of the kinetoplast DNA (kDNA) replication apparatus. These findings resolve two outstanding questions in eukaryote biology: (1) the origin of the unique DNA lesion-recognition component of NER and (2) origin of the unusual, plasmid-like features of kDNA.
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Affiliation(s)
- Arunkumar Krishnan
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - A Maxwell Burroughs
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Lakshminarayan M Iyer
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - L Aravind
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
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12
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Zhang C, Allen KN, Dunaway-Mariano D. Mechanism of Substrate Recognition and Catalysis of the Haloalkanoic Acid Dehalogenase Family Member α-Phosphoglucomutase. Biochemistry 2018; 57:4504-4517. [PMID: 29952545 PMCID: PMC10725300 DOI: 10.1021/acs.biochem.8b00396] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
α-Phosphoglucomutase (αPGM), in its phosphorylated state, catalyzes the interconversion of α-d-glucose 1-phosphate and α-d-glucose 6-phosphate. The αPGM of Lactococcus lactis is a type C2B member of the haloalkanoic acid dehalogenase (HAD) enzyme family and is comprised of a Rossmann-fold catalytic domain and inserted α/β-fold cap domain. The active site is formed at the domain-domain interface. Herein, we report the results from a kinetic-based study of L. lactis αPGM catalysis, which demonstrate enzyme activation by autocatalyzed phosphorylation of Asp8 with αG1P, the intermediacy of αG1,6bisP in the phospho Ll-αPGM-catalyzed conversion of αG1P to G6P, and the reorientation of the αG1,6bisP intermediate via dissociation to solvent and rebinding. In order to provide insight into the structural determinants of L. lactis αPGM substrate recognition and catalysis, metal cofactor and substrate specificities were determined as were the contributions made by active-site residues toward catalytic efficiency. Lastly, the structure and catalytic mechanism of L. lactis αPGM are compared with those of HAD family phosphomutases L. lactis β-phosphoglucomutase and eukayotic α-phosphomannomutase to provide insight into the evolution of phosphohexomutases from HAD family phosphatases.
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Affiliation(s)
- Chunchun Zhang
- Testing & Analytical Center, Sichuan University, Chengdu, Sichuan 610064, P. R. China
| | - Karen N. Allen
- Department of Chemistry, Boston University, Boston MA 02215-2521
| | - Debra Dunaway-Mariano
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131
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13
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Johnson LA, Robertson AJ, Baxter NJ, Trevitt CR, Bisson C, Jin Y, Wood HP, Hounslow AM, Cliff MJ, Blackburn GM, Bowler MW, Waltho JP. van der Waals Contact between Nucleophile and Transferring Phosphorus Is Insufficient To Achieve Enzyme Transition-State Architecture. ACS Catal 2018. [DOI: 10.1021/acscatal.8b01612] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Luke A. Johnson
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Angus J. Robertson
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Nicola J. Baxter
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester M1 7DN, United Kingdom
| | - Clare R. Trevitt
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Claudine Bisson
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Yi Jin
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Henry P. Wood
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Andrea M. Hounslow
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Matthew J. Cliff
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester M1 7DN, United Kingdom
| | - G. Michael Blackburn
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom
| | - Matthew W. Bowler
- European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue des Martyrs, CS 90181, F-38042 Grenoble, France
| | - Jonathan P. Waltho
- Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield S10 2TN, United Kingdom
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, Manchester M1 7DN, United Kingdom
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14
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Ji T, Zhang C, Zheng L, Dunaway-Mariano D, Allen KN. Structural Basis of the Molecular Switch between Phosphatase and Mutase Functions of Human Phosphomannomutase 1 under Ischemic Conditions. Biochemistry 2018; 57:3480-3492. [PMID: 29695157 DOI: 10.1021/acs.biochem.8b00223] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The human phosphomannomutases PMM1 and PMM2 catalyze the interconversion of hexose 6-phosphates and hexose 1-phosphates. The two isoforms share 66% sequence identity and have kinetic properties similar to those of mutases in vitro but differ in their functional roles in vivo. Though the physiological role of PMM2 is catalysis of the mutase reaction that provides the mannose 1-phosphate (Man-1-P) essential for protein glycosylation, PMM1 is thought to provide a phosphohydrolase activity in the presence of inosine monophosphate (IMP), converting glucose 1,6-bisphosphate (Glu-1,6-P2) to glucose 6-phosphate (Glu-6-P), rescuing glycolysis during brain ischemia. To uncover the structural basis of how IMP binding converts PMM1 from a mutase to a phosphatase, the 1.93 Å resolution structure of PMM1 complexed with IMP was determined. The structure reveals IMP bound at the substrate recruitment site, thus inhibiting the mutase activity while simultaneously activating a phosphatase activity (IMP Kact = 1.5 μM) resulting from the hydrolysis of the phospho-enzyme. The bound structure and site-directed mutagenesis confirm that the long-range electrostatic interactions provided by Arg180 and Arg183 conserved in PMM1 are the major contributors to IMP binding, and their oblation removes phosphatase but not mutase activity. These residues are not present in the PMM2 isoform, which consequently lacks significant phosphatase activity in the presence of IMP. T2 relaxation nuclear magnetic resonance and small angle X-ray scattering together support the hypothesis that binding of IMP to PMM1 favors an enzyme conformation that is catalytically competent for water attack at the phosphoaspartyl intermediate. Such a mechanism may be generalizable to other enzymes that act through covalent intermediates.
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Affiliation(s)
- Tianyang Ji
- Department of Chemistry , Boston University , Boston , Massachusetts 02215 , United States
| | - Chunchun Zhang
- Department of Chemistry and Chemical Biology , University of New Mexico , Albuquerque , New Mexico 87131 , United States
| | - Li Zheng
- Department of Chemistry and Chemical Biology , University of New Mexico , Albuquerque , New Mexico 87131 , United States
| | - Debra Dunaway-Mariano
- Department of Chemistry and Chemical Biology , University of New Mexico , Albuquerque , New Mexico 87131 , United States
| | - Karen N Allen
- Department of Chemistry , Boston University , Boston , Massachusetts 02215 , United States
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15
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Mukherjee K, Narindoshvili T, Raushel FM. Discovery of a Kojibiose Phosphorylase in Escherichia coli K-12. Biochemistry 2018; 57:2857-2867. [PMID: 29684280 DOI: 10.1021/acs.biochem.8b00392] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The substrate profiles for three uncharacterized enzymes (YcjM, YcjT, and YcjU) that are expressed from a cluster of 12 genes ( ycjM-W and ompG) of unknown function in Escherichia coli K-12 were determined. Through a comprehensive bioinformatic and steady-state kinetic analysis, the catalytic function of YcjT was determined to be kojibiose phosphorylase. In the presence of saturating phosphate and kojibiose (α-(1,2)-d-glucose-d-glucose), this enzyme catalyzes the formation of d-glucose and β-d-glucose-1-phosphate ( kcat = 1.1 s-1, Km = 1.05 mM, and kcat/ Km = 1.12 × 103 M-1 s-1). Additionally, it was also shown that in the presence of β-d-glucose-1-phosphate, YcjT can catalyze the formation of other disaccharides using 1,5-anhydro-d-glucitol, l-sorbose, d-sorbitol, or l-iditol as a substitute for d-glucose. Kojibiose is a component of cell wall lipoteichoic acids in Gram-positive bacteria and is of interest as a potential low-calorie sweetener and prebiotic. YcjU was determined to be a β-phosphoglucomutase that catalyzes the isomerization of β-d-glucose-1-phosphate ( kcat = 21 s-1, Km = 18 μM, and kcat/ Km = 1.1 × 106 M-1 s-1) to d-glucose-6-phosphate. YcjU was also shown to exhibit catalytic activity with β-d-allose-1-phosphate, β-d-mannose-1-phosphate, and β-d-galactose-1-phosphate. YcjM catalyzes the phosphorolysis of α-(1,2)-d-glucose-d-glycerate with a kcat = 2.1 s-1, Km = 69 μM, and kcat/ Km = 3.1 × 104 M-1 s-1.
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Affiliation(s)
- Keya Mukherjee
- Department of Biochemistry & Biophysics , Texas A&M University , College Station , Texas 77844 , United States
| | - Tamari Narindoshvili
- Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
| | - Frank M Raushel
- Department of Biochemistry & Biophysics , Texas A&M University , College Station , Texas 77844 , United States.,Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
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16
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Park J, Guggisberg AM, Odom AR, Tolia NH. Cap-domain closure enables diverse substrate recognition by the C2-type haloacid dehalogenase-like sugar phosphatase Plasmodium falciparum HAD1. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2015; 71:1824-34. [PMID: 26327372 PMCID: PMC4556313 DOI: 10.1107/s1399004715012067] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 06/23/2015] [Indexed: 11/10/2022]
Abstract
Haloacid dehalogenases (HADs) are a large enzyme superfamily of more than 500,000 members with roles in numerous metabolic pathways. Plasmodium falciparum HAD1 (PfHAD1) is a sugar phosphatase that regulates the methylerythritol phosphate (MEP) pathway for isoprenoid synthesis in malaria parasites. However, the structural determinants for diverse substrate recognition by HADs are unknown. Here, crystal structures were determined of PfHAD1 in complex with three sugar phosphates selected from a panel of diverse substrates that it utilizes. Cap-open and cap-closed conformations are observed, with cap closure facilitating substrate binding and ordering. These structural changes define the role of cap movement within the major subcategory of C2 HAD enzymes. The structures of an HAD bound to multiple substrates identifies binding and specificity-determining residues that define the structural basis for substrate recognition and catalysis within the HAD superfamily. While the substrate-binding region of the cap domain is flexible in the open conformations, this region becomes ordered and makes direct interactions with the substrate in the closed conformations. These studies further inform the structural and biochemical basis for catalysis within a large superfamily of HAD enzymes with diverse functions.
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Affiliation(s)
- Jooyoung Park
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Ann M. Guggisberg
- Department of Pediatrics, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Audrey R. Odom
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO 63110, USA
- Department of Pediatrics, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Niraj H. Tolia
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO 63110, USA
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St Louis, MO 63110, USA
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17
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Panoramic view of a superfamily of phosphatases through substrate profiling. Proc Natl Acad Sci U S A 2015; 112:E1974-83. [PMID: 25848029 DOI: 10.1073/pnas.1423570112] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Large-scale activity profiling of enzyme superfamilies provides information about cellular functions as well as the intrinsic binding capabilities of conserved folds. Herein, the functional space of the ubiquitous haloalkanoate dehalogenase superfamily (HADSF) was revealed by screening a customized substrate library against >200 enzymes from representative prokaryotic species, enabling inferred annotation of ∼35% of the HADSF. An extremely high level of substrate ambiguity was revealed, with the majority of HADSF enzymes using more than five substrates. Substrate profiling allowed assignment of function to previously unannotated enzymes with known structure, uncovered potential new pathways, and identified iso-functional orthologs from evolutionarily distant taxonomic groups. Intriguingly, the HADSF subfamily having the least structural elaboration of the Rossmann fold catalytic domain was the most specific, consistent with the concept that domain insertions drive the evolution of new functions and that the broad specificity observed in HADSF may be a relic of this process.
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18
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Pandya C, Farelli JD, Dunaway-Mariano D, Allen KN. Enzyme promiscuity: engine of evolutionary innovation. J Biol Chem 2014; 289:30229-30236. [PMID: 25210039 DOI: 10.1074/jbc.r114.572990] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Catalytic promiscuity and substrate ambiguity are keys to evolvability, which in turn is pivotal to the successful acquisition of novel biological functions. Action on multiple substrates (substrate ambiguity) can be harnessed for performance of functions in the cell that supersede catalysis of a single metabolite. These functions include proofreading, scavenging of nutrients, removal of antimetabolites, balancing of metabolite pools, and establishing system redundancy. In this review, we present examples of enzymes that perform these cellular roles by leveraging substrate ambiguity and then present the structural features that support both specificity and ambiguity. We focus on the phosphatases of the haloalkanoate dehalogenase superfamily and the thioesterases of the hotdog fold superfamily.
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Affiliation(s)
- Chetanya Pandya
- Bioinformatics Graduate Program and Boston University, Boston, Massachusetts 02215
| | - Jeremiah D Farelli
- Department of Chemistry, Boston University, Boston, Massachusetts 02215 and
| | - Debra Dunaway-Mariano
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131.
| | - Karen N Allen
- Bioinformatics Graduate Program and Boston University, Boston, Massachusetts 02215; Department of Chemistry, Boston University, Boston, Massachusetts 02215 and.
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19
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Jin Y, Bhattasali D, Pellegrini E, Forget SM, Baxter NJ, Cliff MJ, Bowler MW, Jakeman DL, Blackburn GM, Waltho JP. α-Fluorophosphonates reveal how a phosphomutase conserves transition state conformation over hexose recognition in its two-step reaction. Proc Natl Acad Sci U S A 2014; 111:12384-9. [PMID: 25104750 PMCID: PMC4151737 DOI: 10.1073/pnas.1402850111] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
β-Phosphoglucomutase (βPGM) catalyzes isomerization of β-D-glucose 1-phosphate (βG1P) into D-glucose 6-phosphate (G6P) via sequential phosphoryl transfer steps using a β-D-glucose 1,6-bisphosphate (βG16BP) intermediate. Synthetic fluoromethylenephosphonate and methylenephosphonate analogs of βG1P deliver novel step 1 transition state analog (TSA) complexes for βPGM, incorporating trifluoromagnesate and tetrafluoroaluminate surrogates of the phosphoryl group. Within an invariant protein conformation, the β-D-glucopyranose ring in the βG1P TSA complexes (step 1) is flipped over and shifted relative to the G6P TSA complexes (step 2). Its equatorial hydroxyl groups are hydrogen-bonded directly to the enzyme rather than indirectly via water molecules as in step 2. The (C)O-P bond orientation for binding the phosphate in the inert phosphate site differs by ∼ 30° between steps 1 and 2. By contrast, the orientations for the axial O-Mg-O alignment for the TSA of the phosphoryl group in the catalytic site differ by only ∼ 5°, and the atoms representing the five phosphorus-bonded oxygens in the two transition states (TSs) are virtually superimposable. The conformation of βG16BP in step 1 does not fit into the same invariant active site for step 2 by simple positional interchange of the phosphates: the TS alignment is achieved by conformational change of the hexose rather than the protein.
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Affiliation(s)
- Yi Jin
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom
| | - Debabrata Bhattasali
- Department of Chemistry, College of Pharmacy, Dalhousie University, Halifax, NS, Canada B3H 4R2
| | - Erika Pellegrini
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom; Structural Biology Group, European Synchrotron Radiation Facility, 38042 Grenoble, Cedex 9, France; European Molecular Biology Laboratory, Grenoble Outstation, 38042 Grenoble, Cedex 9, France
| | - Stephanie M Forget
- Department of Chemistry, College of Pharmacy, Dalhousie University, Halifax, NS, Canada B3H 4R2
| | - Nicola J Baxter
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom
| | - Matthew J Cliff
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom; Manchester Institute of Biotechnology, Manchester M1 7DN, United Kingdom; and
| | - Matthew W Bowler
- Structural Biology Group, European Synchrotron Radiation Facility, 38042 Grenoble, Cedex 9, France; European Molecular Biology Laboratory, Grenoble Outstation, 38042 Grenoble, Cedex 9, France; Unit of Virus Host Cell Interactions, University of Grenoble Alpes-European Molecular Biology Laboratory-Centre National de la Recherche Scientifique, 38042 Grenoble, Cedex 9, France
| | - David L Jakeman
- Department of Chemistry, College of Pharmacy, Dalhousie University, Halifax, NS, Canada B3H 4R2;
| | - G Michael Blackburn
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom;
| | - Jonathan P Waltho
- Department of Molecular Biology and Biotechnology, Krebs Institute, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom; Manchester Institute of Biotechnology, Manchester M1 7DN, United Kingdom; and
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20
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Identification and characterization of an archaeal kojibiose catabolic pathway in the hyperthermophilic Pyrococcus sp. strain ST04. J Bacteriol 2014; 196:1122-31. [PMID: 24391053 DOI: 10.1128/jb.01222-13] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
A unique gene cluster responsible for kojibiose utilization was identified in the genome of Pyrococcus sp. strain ST04. The proteins it encodes hydrolyze kojibiose, a disaccharide product of glucose caramelization, and form glucose-6-phosphate (G6P) in two steps. Heterologous expression of the kojibiose-related enzymes in Escherichia coli revealed that two genes, Py04_1502 and Py04_1503, encode kojibiose phosphorylase (designated PsKP, for Pyrococcus sp. strain ST04 kojibiose phosphorylase) and β-phosphoglucomutase (PsPGM), respectively. Enzymatic assays show that PsKP hydrolyzes kojibiose to glucose and β-glucose-1-phosphate (β-G1P). The Km values for kojibiose and phosphate were determined to be 2.53 ± 0.21 mM and 1.34 ± 0.04 mM, respectively. PsPGM then converts β-G1P into G6P in the presence of 6 mM MgCl2. Conversion activity from β-G1P to G6P was 46.81 ± 3.66 U/mg, and reverse conversion activity from G6P to β-G1P was 3.51 ± 0.13 U/mg. The proteins are highly thermostable, with optimal temperatures of 90°C for PsKP and 95°C for PsPGM. These results indicate that Pyrococcus sp. strain ST04 converts kojibiose into G6P, a substrate of the glycolytic pathway. This is the first report of a disaccharide utilization pathway via phosphorolysis in hyperthermophilic archaea.
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21
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Nogly P, Matias PM, de Rosa M, Castro R, Santos H, Neves AR, Archer M. High-resolution structure of an atypical α-phosphoglucomutase related to eukaryotic phosphomannomutases. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2013; 69:2008-16. [DOI: 10.1107/s0907444913017046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 06/19/2013] [Indexed: 11/10/2022]
Abstract
The first structure of a bacterial α-phosphoglucomutase with an overall fold similar to eukaryotic phosphomannomutases is reported. Unlike most α-phosphoglucomutases within the α-D-phosphohexomutase superfamily, it belongs to subclass IIb of the haloacid dehalogenase superfamily (HADSF). It catalyzes the reversible conversion of α-glucose 1-phosphate to glucose 6-phosphate. The crystal structure of α-phosphoglucomutase fromLactococcus lactis(APGM) was determined at 1.5 Å resolution and contains a sulfate and a glycerol bound at the enzyme active site that partially mimic the substrate. A dimeric form of APGM is present in the crystal and in solution, an arrangement that may be functionally relevant. The catalytic mechanism of APGM and its strict specificity towards α-glucose 1-phosphate are discussed.
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22
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Theoretical investigation of the enzymatic phosphoryl transfer of β-phosphoglucomutase: revisiting both steps of the catalytic cycle. J Mol Model 2012; 18:3169-79. [PMID: 22238068 DOI: 10.1007/s00894-011-1344-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Accepted: 12/19/2011] [Indexed: 10/14/2022]
Abstract
Enzyme catalyzed phosphate transfer is a part of almost all metabolic processes. Such reactions are of central importance for the energy balance in all organisms and play important roles in cellular control at all levels. Mutases transfer a phosphoryl group while nucleases cleave the phosphodiester linkages between two nucleotides. The subject of our present study is the Lactococcus lactis β-phosphoglucomutase (β-PGM), which effectively catalyzes the interconversion of β-D-glucose-1-phosphate (β-G1P) to β-D-glucose-6-phosphate (β-G6P) and vice versa via stabile intermediate β-D-glucose-1,6-(bis)phosphate (β-G1,6diP) in the presence of Mg(2+). In this paper we revisited the reaction mechanism of the phosphoryl transfer starting from the bisphosphate β-G1,6diP in both directions (toward β-G1P and β-G6P) combining docking techniques and QM/MM theoretical method at the DFT/PBE0 level of theory. In addition we performed NEB (nudged elastic band) and free energy calculations to optimize the path and to identify the transition states and the energies involved in the catalytic cycle. Our calculations reveal that both steps proceed via dissociative pentacoordinated phosphorane, which is not a stabile intermediate but rather a transition state. In addition to the Mg(2+) ion, Ser114 and Lys145 also play important roles in stabilizing the large negative charge on the phosphate through strong coordination with the phosphate oxygens and guiding the phosphate group throughout the catalytic process. The calculated energy barrier of the reaction for the β-G1P to β-G1,6diP step is only slightly higher than for the β-G1,6diP to β-G6P step (16.10 kcal mol(-1) versus 15.10 kcal mol(-1)) and is in excellent agreement with experimental findings (14.65 kcal mol(-1)).
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23
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Lu Z, Dunaway-Mariano D, Allen KN. The X-ray crystallographic structure and specificity profile of HAD superfamily phosphohydrolase BT1666: comparison of paralogous functions in B. thetaiotaomicron. Proteins 2011; 79:3099-107. [PMID: 21989931 DOI: 10.1002/prot.23137] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Revised: 05/26/2011] [Accepted: 06/23/2011] [Indexed: 11/06/2022]
Abstract
Analysis of the haloalkanoate dehalogenase superfamily (HADSF) has uncovered homologues occurring within the same organism that are found to possess broad, overlapping substrate specificities, and low catalytic efficiencies. Here we compare the HADSF phosphatase BT1666 from Bacteroides thetaiotaomicron VPI-5482 to a homologue with high sequence identity (40%) from the same organism BT4131, a known hexose-phosphate phosphatase. The goal is to find whether these enzymes represent duplicated versus paralogous activities. The X-ray crystal structure of BT1666 was determined to 1.82 Å resolution. Superposition of the BT1666 and BT4131 structures revealed a conserved fold and identical active sites suggestive of a common physiological substrate. The steady-state kinetic constants for BT1666 were determined for a diverse panel of phosphorylated metabolites to define its substrate specificity profile and overall level of catalytic efficiency. Whereas BT1666 and BT4131 are both promiscuous, their substrate specificity profiles are distinct. The catalytic efficiency of BT1666 (k(cat) /K(m) = 4.4 × 10(2) M(-1) s(-1) for the best substrate fructose 1,6-(bis)phosphate) is an order of magnitude less than that of BT4131 (k(cat) /K(m) = 6.7 × 10(3) M(-1) s(-1) for 2-deoxyglucose 6-phosphate). The seemingly identical active-site structures point to sequence variation outside the active site causing differences in conformational dynamics or subtle catalytic positioning effects that drive the divergence in catalytic efficiency and selectivity. The overlapping substrate profiles may be understood in terms of differential regulation of expression of the two enzymes or a conferred advantage in metabolic housekeeping functions by having a larger range of possible metabolites as substrates.
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Affiliation(s)
- Zhibing Lu
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, USA
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24
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Panosian TD, Nannemann DP, Watkins GR, Phelan VV, McDonald WH, Wadzinski BE, Bachmann BO, Iverson TM. Bacillus cereus phosphopentomutase is an alkaline phosphatase family member that exhibits an altered entry point into the catalytic cycle. J Biol Chem 2011; 286:8043-8054. [PMID: 21193409 PMCID: PMC3048691 DOI: 10.1074/jbc.m110.201350] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2010] [Revised: 12/14/2010] [Indexed: 11/06/2022] Open
Abstract
Bacterial phosphopentomutases (PPMs) are alkaline phosphatase superfamily members that interconvert α-D-ribose 5-phosphate (ribose 5-phosphate) and α-D-ribose 1-phosphate (ribose 1-phosphate). We investigated the reaction mechanism of Bacillus cereus PPM using a combination of structural and biochemical studies. Four high resolution crystal structures of B. cereus PPM revealed the active site architecture, identified binding sites for the substrate ribose 5-phosphate and the activator α-D-glucose 1,6-bisphosphate (glucose 1,6-bisphosphate), and demonstrated that glucose 1,6-bisphosphate increased phosphorylation of the active site residue Thr-85. The phosphorylation of Thr-85 was confirmed by Western and mass spectroscopic analyses. Biochemical assays identified Mn(2+)-dependent enzyme turnover and demonstrated that glucose 1,6-bisphosphate treatment increases enzyme activity. These results suggest that protein phosphorylation activates the enzyme, which supports an intermolecular transferase mechanism. We confirmed intermolecular phosphoryl transfer using an isotope relay assay in which PPM reactions containing mixtures of ribose 5-[(18)O(3)]phosphate and [U-(13)C(5)]ribose 5-phosphate were analyzed by mass spectrometry. This intermolecular phosphoryl transfer is seemingly counter to what is anticipated from phosphomutases employing a general alkaline phosphatase reaction mechanism, which are reported to catalyze intramolecular phosphoryl transfer. However, the two mechanisms may be reconciled if substrate encounters the enzyme at a different point in the catalytic cycle.
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Affiliation(s)
| | - David P Nannemann
- the Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235
| | | | - Vanessa V Phelan
- the Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235
| | - W Hayes McDonald
- Biochemistry, Vanderbilt University Medical Center, Nashville, Tennessee 37232 and
| | | | - Brian O Bachmann
- the Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235; Biochemistry, Vanderbilt University Medical Center, Nashville, Tennessee 37232 and.
| | - Tina M Iverson
- From the Departments of Pharmacology and; Biochemistry, Vanderbilt University Medical Center, Nashville, Tennessee 37232 and.
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25
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Focus on phosphoaspartate and phosphoglutamate. Amino Acids 2010; 40:1035-51. [DOI: 10.1007/s00726-010-0738-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2010] [Accepted: 08/27/2010] [Indexed: 11/26/2022]
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26
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Allen KN, Dunaway-Mariano D. Markers of fitness in a successful enzyme superfamily. Curr Opin Struct Biol 2009; 19:658-65. [PMID: 19889535 DOI: 10.1016/j.sbi.2009.09.008] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2009] [Revised: 09/25/2009] [Accepted: 09/30/2009] [Indexed: 11/17/2022]
Abstract
Haloalkanoic acid dehalogenase (HAD) superfamily members serve as the predominant catalysts of metabolic phosphate ester hydrolysis in all three superkingdoms of life. Collectively, the known structural, bioinformatic, and mechanistic data offer a glimpse of the variety of HAD enzymes that have evolved in the service of metabolic expansion. Factors that have contributed to superfamily dominance include a chemically versatile nucleophile, stability of the core superfold, structural modularity of the chemistry and specificity domains, conformational coupling conferred by the topology of the inserted specificity elements, and retention of a conserved mold for stabilization of the trigonal bipyramidal transition state.
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Affiliation(s)
- Karen N Allen
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, MA 02215-2521, USA.
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27
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Dai J, Finci L, Zhang C, Lahiri S, Zhang G, Peisach E, Allen KN, Dunaway-Mariano D. Analysis of the structural determinants underlying discrimination between substrate and solvent in beta-phosphoglucomutase catalysis. Biochemistry 2009; 48:1984-95. [PMID: 19154134 DOI: 10.1021/bi801653r] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Tauhe beta-phosphoglucomutase (beta-PGM) of the haloacid dehalogenase enzyme superfamily (HADSF) catalyzes the conversion of beta-glucose 1-phosphate (betaG1P) to glucose 6-phosphate (G6P) using Asp8 of the core domain active site to mediate phosphoryl transfer from beta-glucose 1,6-(bis)phosphate (betaG1,6bisP) to betaG1P. Herein, we explore the mechanism by which hydrolysis of the beta-PGM phospho-Asp8 is avoided during the time that the active site must remain open to solvent to allow the exchange of the bound product G6P with the substrate betaG1P. On the basis of structural information, a model of catalysis is proposed in which the general acid/base (Asp10) side chain moves from a position where it forms a hydrogen bond to the Thr16-Ala17 portion of the domain-domain linker to a functional position where it forms a hydrogen bond to the substrate leaving group O and a His20-Lys76 pair of the cap domain. This repositioning of the general acid/base within the core domain active site is coordinated with substrate-induced closure of the cap domain over the core domain. The model predicts that Asp10 is required for general acid/base catalysis and for stabilization of the enzyme in the cap-closed conformation. It also predicts that hinge residue Thr16 plays a key role in productive domain-domain association, that hydrogen bond interaction with the Thr16 backbone amide NH group is required to prevent phospho-Asp8 hydrolysis in the cap-open conformation, and that the His20-Lys76 pair plays an important role in substrate-induced cap closure. The model is examined via kinetic analyses of Asp10, Thr16, His20, and Lys76 site-directed mutants. Replacement of Asp10 with Ala, Ser, Cys, Asn, or Glu resulted in no observable activity. The kinetic consequences of the replacement of linker residue Thr16 with Pro include a reduced rate of Asp8 phosphorylation by betaG1,6bisP, a reduced rate of cycling of the phosphorylated enzyme to convert betaG1P to G6P, and an enhanced rate of phosphoryl transfer from phospho-Asp8 to water. The X-ray crystal structure of the T16P mutant at 2.7 A resolution provides a snapshot of the enzyme in an unnatural cap-open conformation where the Asp10 side chain is located in the core domain active site. The His20 and Lys76 site-directed mutants exhibit reduced activity in catalysis of the Asp8-mediated phosphoryl transfer between betaG1,6bisP and betaG1P but no reduction in the rate of phospho-Asp8 hydrolysis. Taken together, the results support a substrate induced-fit model of catalysis in which betaG1P binding to the core domain facilitates recruitment of the general acid/base Asp10 to the catalytic site and induces cap closure.
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Affiliation(s)
- Jianying Dai
- Department of Chemistry, University of New Mexico, Albuquerque, New Mexico 87131, USA
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28
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Golicnik M, Olguin LF, Feng G, Baxter NJ, Waltho JP, Williams NH, Hollfelder F. Kinetic analysis of beta-phosphoglucomutase and its inhibition by magnesium fluoride. J Am Chem Soc 2009; 131:1575-88. [PMID: 19132841 DOI: 10.1021/ja806421f] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The isomerization of beta-glucose-1-phosphate (betaG1P) to beta-glucose-6-phosphate (G6P) catalyzed by beta-phosphoglucomutase (betaPGM) has been examined using steady- and presteady-state kinetic analysis. In the presence of low concentrations of beta-glucose-1,6-bisphosphate (betaG16BP), the reaction proceeds through a Ping Pong Bi Bi mechanism with substrate inhibition (kcat = 65 s(-1), K(betaG1P) = 15 microM, K(betaG16BP) = 0.7 microM, Ki = 122 microM). If alphaG16BP is used as a cofactor, more complex kinetic behavior is observed, but the nonlinear progress curves can be fit to reveal further catalytic parameters (kcat = 74 s(-1), K(betaG1P) = 15 microM, K(betaG16BP) = 0.8 microM, Ki = 122 microM, K(alphaG16BP) = 91 microM for productive binding, K(alphaG16BP) = 21 microM for unproductive binding). These data reveal that variations in the substrate structure affect transition-state affinity (approximately 140,000-fold in terms of rate acceleration) substantially more than ground-state binding (110-fold in terms of binding affinity). When fluoride and magnesium ions are present, time-dependent inhibition of the betaPGM is observed. The concentration dependence of the parameters obtained from fitting these progress curves shows that a betaG1P x MgF3(-) x betaPGM inhibitory complex is formed under the reaction conditions. The overall stability constant for this complex is approximately 2 x 10(-16) M(5) and suggests an affinity of the MgF3(-) moiety to this transition-state analogue (TSA) of < or = 70 nM. The detailed kinetic analysis shows how a special type of TSA that does not exist in solution is assembled in the active site of an enzyme. Further experiments show that under the conditions of previous structural studies, phosphorylated glucose only persists when bound to the enzyme as the TSA. The preference for TSA formation when fluoride is present, and the hydrolysis of substrates when it is not, rules out the formation of a stable pentavalent phosphorane intermediate in the active site of betaPGM.
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Affiliation(s)
- Marko Golicnik
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, United Kingdom
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29
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The catalytic scaffold of the haloalkanoic acid dehalogenase enzyme superfamily acts as a mold for the trigonal bipyramidal transition state. Proc Natl Acad Sci U S A 2008; 105:5687-92. [PMID: 18398008 DOI: 10.1073/pnas.0710800105] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The evolution of new catalytic activities and specificities within an enzyme superfamily requires the exploration of sequence space for adaptation to a new substrate with retention of those elements required to stabilize key intermediates/transition states. Here, we propose that core residues in the large enzyme family, the haloalkanoic acid dehalogenase enzyme superfamily (HADSF) form a "mold" in which the trigonal bipyramidal transition states formed during phosphoryl transfer are stabilized by electrostatic forces. The vanadate complex of the hexose phosphate phosphatase BT4131 from Bacteroides thetaiotaomicron VPI-5482 (HPP) determined at 1.00 A resolution via X-ray crystallography assumes a trigonal bipyramidal coordination geometry with the nucleophilic Asp-8 and one oxygen ligand at the apical position. Remarkably, the tungstate in the complex determined to 1.03 A resolution assumes the same coordination geometry. The contribution of the general acid/base residue Asp-10 in the stabilization of the trigonal bipyramidal species via hydrogen-bond formation with the apical oxygen atom is evidenced by the 1.52 A structure of the D10A mutant bound to vanadate. This structure shows a collapse of the trigonal bipyramidal geometry with displacement of the water molecule formerly occupying the apical position. Furthermore, the 1.07 A resolution structure of the D10A mutant complexed with tungstate shows the tungstate to be in a typical "phosphate-like" tetrahedral configuration. The analysis of 12 liganded HADSF structures deposited in the protein data bank (PDB) identified stringently conserved elements that stabilize the trigonal bipyramidal transition states by engaging in favorable electrostatic interactions with the axial and equatorial atoms of the transferring phosphoryl group.
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Kedzierski L, Malby RL, Smith BJ, Perugini MA, Hodder AN, Ilg T, Colman PM, Handman E. Structure of Leishmania mexicana Phosphomannomutase Highlights Similarities with Human Isoforms. J Mol Biol 2006; 363:215-27. [PMID: 16963079 DOI: 10.1016/j.jmb.2006.08.023] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2006] [Revised: 08/04/2006] [Accepted: 08/10/2006] [Indexed: 11/18/2022]
Abstract
Phosphomannomutase (PMM) catalyses the conversion of mannose-6-phosphate to mannose-1-phosphate, an essential step in mannose activation and the biosynthesis of glycoconjugates in all eukaryotes. Deletion of PMM from Leishmania mexicana results in loss of virulence, suggesting that PMM is a promising drug target for the development of anti-leishmanial inhibitors. We report the crystallization and structure determination to 2.1 A of L. mexicana PMM alone and in complex with glucose-1,6-bisphosphate to 2.9 A. PMM is a member of the haloacid dehalogenase (HAD) family, but has a novel dimeric structure and a distinct cap domain of unique topology. Although the structure is novel within the HAD family, the leishmanial enzyme shows a high degree of similarity with its human isoforms. We have generated L. major PMM knockouts, which are avirulent. We expressed the human pmm2 gene in the Leishmania PMM knockout, but despite the similarity between Leishmania and human PMM, expression of the human gene did not restore virulence. Similarities in the structure of the parasite enzyme and its human isoforms suggest that the development of parasite-selective inhibitors will not be an easy task.
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Affiliation(s)
- Lukasz Kedzierski
- Infection and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
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