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Chen J, Wu H, Zhang W, Mu W. Ribose-5-phosphate isomerases: characteristics, structural features, and applications. Appl Microbiol Biotechnol 2020; 104:6429-6441. [PMID: 32533303 DOI: 10.1007/s00253-020-10735-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 06/02/2020] [Accepted: 06/07/2020] [Indexed: 01/21/2023]
Abstract
Ribose-5-phosphate isomerase (Rpi, EC 5.3.1.6) is widespread in microorganisms, animals, and plants. It has a pivotal role in the pentose phosphate pathway and responsible for catalyzing the isomerization between D-ribulose 5-phosphate and D-ribose 5-phosphate. In recent years, Rpi has received considerable attention as a multipurpose biocatalyst for production of rare sugars, including D-allose, L-rhamnulose, L-lyxose, and L-tagatose. Besides, it has been thought of as a potential drug target in the treatment of trypanosomatid-caused diseases such as Chagas' disease, leishmaniasis, and human African trypanosomiasis. Despite increased research activities, up to now, no systematic review of Rpi has been published. To fill this gap, this paper provides detailed information about the enzymatic properties of various Rpis. Furthermore, structural features, catalytic mechanism, and molecular modifications of Rpis are summarized based on extensive crystal structure research. Additionally, the applications of Rpi in rare sugar production and the role of Rpi in trypanocidal drug design are reviewed. Key points • Fundamental properties of various ribose-5-phosphate isomerases (Rpis). • Differences in crystal structure and catalytic mechanism between RpiA and RpiB. • Application of Rpi as a rare sugar producer and a potential drug target.
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Affiliation(s)
- Jiajun Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Hao Wu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China.
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, 214122, Jiangsu, China.
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, 214122, Jiangsu, China
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2
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Wang J, Yang W. Concerted proton transfer mechanism of Clostridium thermocellum ribose-5-phosphate isomerase. J Phys Chem B 2013; 117:9354-61. [PMID: 23875675 PMCID: PMC3772085 DOI: 10.1021/jp404948c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ribose-5-phosphate isomerase (Rpi) catalyzes the interconversion of D-ribose-5-phosphate and D-ribulose-5-phosphate and plays an essential role in the pentose phosphate pathway and the Calvin cycle of photosynthesis. RpiB, one of the two isoforms of Rpi, is also a potential drug target for some pathogenic bacteria. Clostridium thermocellum ribose-5-phosphate isomerase (CtRpi), belonging to the RpiB family, has recently been employed in the industrial production of rare sugars because of its fast reaction kinetics and narrow substrate specificity. It is known that this enzyme adopts a proton transfer mechanism. It was suggested that the deprotonated Cys65 attracts the proton at C2 of the substrate to initiate the isomerization reaction, and this step is the rate-limiting step. However the elaborate catalytic mechanism is still unclear. We have performed quantum mechanical/molecular mechanical simulations of this rate-limiting step of the reaction catalyzed by CtRpi with the substrate D-ribose. Our results demonstrate that the deprotonated Cys65 is not a stable reactant. Instead, our calculations revealed a concerted proton-transfer mechanism: Asp8, a highly conserved residue in the RpiB family, performs as the base to abstract the proton at Cys65 and Cys65 in turn abstracting the proton of the D-ribose simultaneously. Moreover, we found Thr67 cannot catalyze the proton transfer from O2 to O1 of the D-ribose alone. Water molecule(s) may assist this proton transfer with Thr67. Our findings lead to a clear understanding of the catalysis mechanism of the RpiB family and should guide experiments to increase the catalysis efficiency. This study also highlights the importance of initial protonation states of cysteines.
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Affiliation(s)
- Jun Wang
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Weitao Yang
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
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3
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Lobley CMC, Aller P, Douangamath A, Reddivari Y, Bumann M, Bird LE, Nettleship JE, Brandao-Neto J, Owens RJ, O’Toole PW, Walsh MA. Structure of ribose 5-phosphate isomerase from the probiotic bacterium Lactobacillus salivarius UCC118. Acta Crystallogr Sect F Struct Biol Cryst Commun 2012; 68:1427-33. [PMID: 23192019 PMCID: PMC3509960 DOI: 10.1107/s174430911204273x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Accepted: 10/12/2012] [Indexed: 11/10/2022]
Abstract
The structure of ribose 5-phosphate isomerase from the probiotic bacterium Lactobacillus salivarius UCC188 has been determined at 1.72 Å resolution. The structure was solved by molecular replacement, which identified the functional homodimer in the asymmetric unit. Despite only showing 57% sequence identity to its closest homologue, the structure adopted the typical α and β D-ribose 5-phosphate isomerase fold. Comparison to other related structures revealed high homology in the active site, allowing a model of the substrate-bound protein to be proposed. The determination of the structure was expedited by the use of in situ crystallization-plate screening on beamline I04-1 at Diamond Light Source to identify well diffracting protein crystals prior to routine cryocrystallography.
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Affiliation(s)
- Carina M. C. Lobley
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, England
| | - Pierre Aller
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, England
| | - Alice Douangamath
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, England
| | - Yamini Reddivari
- Oxford Protein Production Facility UK, Research Complex at Harwell, R92 Rutherford Appleton Laboratories, Harwell, Oxfordshire OX11 0FA, England
| | - Mario Bumann
- MRC France, BM14, c/o ESRF, 6 Rue Jules Horowitz, BP 220, 38043 Grenoble France
| | - Louise E. Bird
- Oxford Protein Production Facility UK, Research Complex at Harwell, R92 Rutherford Appleton Laboratories, Harwell, Oxfordshire OX11 0FA, England
| | - Joanne E. Nettleship
- Oxford Protein Production Facility UK, Research Complex at Harwell, R92 Rutherford Appleton Laboratories, Harwell, Oxfordshire OX11 0FA, England
| | - Jose Brandao-Neto
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, England
| | - Raymond J. Owens
- Oxford Protein Production Facility UK, Research Complex at Harwell, R92 Rutherford Appleton Laboratories, Harwell, Oxfordshire OX11 0FA, England
| | - Paul W. O’Toole
- Department of Microbiology, Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
| | - Martin A. Walsh
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, England
- MRC France, BM14, c/o ESRF, 6 Rue Jules Horowitz, BP 220, 38043 Grenoble France
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Thermophilic Thermotoga maritima ribose-5-phosphate isomerase RpiB: optimized heat treatment purification and basic characterization. Protein Expr Purif 2012; 82:302-7. [PMID: 22333529 DOI: 10.1016/j.pep.2012.01.017] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Revised: 01/26/2012] [Accepted: 01/28/2012] [Indexed: 11/21/2022]
Abstract
The open reading frame TM1080 from Thermotoga maritima encoding ribose-5-phosphate isomerase type B (RpiB) was cloned and over-expressed in Escherichia coli BL21 (DE3). After optimization of cell culture conditions, more than 30% of intracellular proteins were soluble recombinant RpiB. High-purity RpiB was obtained by heat pretreatment through its optimization in buffer choice, buffer pH, as well as temperature and duration of pretreatment. This enzyme had the maximum activity at 70°C and pH 6.5-8.0. Under its suboptimal conditions (60°C and pH 7.0), k(cat) and K(m) values were 540s(-1) and 7.6mM, respectively; it had a half lifetime of 71h, resulting in its turn-over number of more than 2×10(8)mol of product per mol of enzyme. This study suggests that it is highly feasible to discover thermostable enzymes from exploding genomic DNA database of extremophiles with the desired stability suitable for in vitro synthetic biology projects and produce high-purity thermoenzymes at very low costs.
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Edwards TE, Abramov AB, Smith ER, Baydo RO, Leonard JT, Leibly DJ, Thompkins KB, Clifton MC, Gardberg AS, Staker BL, Van Voorhis WC, Myler PJ, Stewart LJ. Structural characterization of a ribose-5-phosphate isomerase B from the pathogenic fungus Coccidioides immitis. BMC STRUCTURAL BIOLOGY 2011; 11:39. [PMID: 21995815 PMCID: PMC3212906 DOI: 10.1186/1472-6807-11-39] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 10/13/2011] [Indexed: 01/01/2023]
Abstract
BACKGROUND Ribose-5-phosphate isomerase is an enzyme that catalyzes the interconversion of ribose-5-phosphate and ribulose-5-phosphate. This family of enzymes naturally occurs in two distinct classes, RpiA and RpiB, which play an important role in the pentose phosphate pathway and nucleotide and co-factor biogenesis. RESULTS Although RpiB occurs predominantly in bacteria, here we report crystal structures of a putative RpiB from the pathogenic fungus Coccidioides immitis. A 1.9 Å resolution apo structure was solved by combined molecular replacement and single wavelength anomalous dispersion (SAD) phasing using a crystal soaked briefly in a solution containing a high concentration of iodide ions. RpiB from C. immitis contains modest sequence and high structural homology to other known RpiB structures. A 1.8 Å resolution phosphate-bound structure demonstrates phosphate recognition and charge stabilization by a single positively charged residue whereas other members of this family use up to five positively charged residues to contact the phosphate of ribose-5-phosphate. A 1.7 Å resolution structure was obtained in which the catalytic base of C. immitis RpiB, Cys76, appears to form a weakly covalent bond with the central carbon of malonic acid with a bond distance of 2.2 Å. This interaction may mimic that formed by the suicide inhibitor iodoacetic acid with RpiB. CONCLUSION The C. immitis RpiB contains the same fold and similar features as other members of this class of enzymes such as a highly reactive active site cysteine residue, but utilizes a divergent phosphate recognition strategy and may recognize a different substrate altogether.
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Affiliation(s)
- Thomas E Edwards
- Seattle Structural Genomics Center for Infectious Disease (SSGCID), USA.
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Stern AL, Naworyta A, Cazzulo JJ, Mowbray SL. Structures of type B ribose 5-phosphate isomerase from Trypanosoma cruzi shed light on the determinants of sugar specificity in the structural family. FEBS J 2011; 278:793-808. [PMID: 21205211 DOI: 10.1111/j.1742-4658.2010.07999.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ribose-5-phosphate isomerase (Rpi; EC 5.3.1.6) is a key activity of the pentose phosphate pathway. Two unrelated types of sequence/structure possess this activity: type A Rpi (present in most organisms) and type B Rpi (RpiB) (in some bacteria and parasitic protozoa). In the present study, we report enzyme kinetics and crystallographic studies of the RpiB from the human pathogen, Trypanosoma cruzi. Structures of the wild-type and a Cys69Ala mutant enzyme, alone or bound to phosphate, D-ribose 5-phosphate, or the inhibitors 4-phospho-D-erythronohydroxamic acid and D-allose 6-phosphate, highlight features of the active site, and show that small conformational changes are linked to binding. Kinetic studies confirm that, similar to the RpiB from Mycobacterium tuberculosis, the T. cruzi enzyme can isomerize D-ribose 5-phosphate effectively, but not the 6-carbon sugar D-allose 6-phosphate; instead, this sugar acts as an inhibitor of both enzymes. The behaviour is distinct from that of the more closely related (to T. cruzi RpiB) Escherichia coli enzyme, which can isomerize both types of sugars. The hypothesis that differences in a phosphate-binding loop near the active site were linked to the differences in specificity was tested by construction of a mutant T. cruzi enzyme with a sequence in this loop more similar to that of E. coli RpiB; this mutant enzyme gained the ability to act on the 6-carbon sugar. The combined information allows us to distinguish the two types of specificity patterns in other available sequences. The results obtained in the present study provide insights into the action of RpiB enzymes generally, and also comprise a firm basis for future work in drug design.
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Affiliation(s)
- Ana L Stern
- Department of Molecular Biology, Swedish University of Agricultural Sciences, Uppsala, Sweden
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Jung J, Kim JK, Yeom SJ, Ahn YJ, Oh DK, Kang LW. Crystal structure of Clostridium thermocellum ribose-5-phosphate isomerase B reveals properties critical for fast enzyme kinetics. Appl Microbiol Biotechnol 2011; 90:517-27. [PMID: 21253719 DOI: 10.1007/s00253-011-3095-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 12/21/2010] [Accepted: 01/03/2011] [Indexed: 11/27/2022]
Abstract
Ribose-5-phosphate isomerase (Rpi) catalyzes the conversion of D-ribose 5-phosphate (R5P) to D-ribulose 5-phosphate, which is an important step in the non-oxidative pathway of the pentose phosphate pathway and the Calvin cycle of photosynthesis. Recently, Rpis have been used to produce valuable rare sugars for industrial purposes. Of the Rpis, D-ribose-5-phosphate isomerase B from Clostridium thermocellum (CtRpi) has the fastest reactions kinetics. While Thermotoga maritime Rpi (TmRpi) has the same substrate specificity as CtRpi, the overall activity of CtRpi is approximately 200-fold higher than that of TmRpi. To understand the structural basis of these kinetic differences, we determined the crystal structures, at 2.1-Å resolution or higher, of CtRpi alone and bound to its substrates, R5P, D-ribose, and D-allose. Structural comparisons of CtRpi and TmRpi showed overall conservation of their structures with two notable differences. First, the volume of the CtRpi substrate binding pocket (SBP) was 20% less than that of the TmRpi SBP. Second, the residues next to the sugar-ring opening catalytic residue (His98) were different. We switched the key residues, involved in SBP shaping or catalysis, between CtRpi and TmRpi by site-directed mutagenesis, and studied the enzyme kinetics of the mutants. We found that tight interactions between the two monomers, narrow SBP width, and the residues near the catalytic residue are all critical for the fast enzyme kinetics of CtRpi.
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Affiliation(s)
- Junho Jung
- Department of Advanced Technology Fusion, Konkuk University, Hwayang dong, Gwangjin-gu, Seoul 143-701, South Korea
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8
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Yeom SJ, Seo ES, Kim YS, Oh DK. Increased D-allose production by the R132E mutant of ribose-5-phosphate isomerase from Clostridium thermocellum. Appl Microbiol Biotechnol 2010; 89:1859-66. [PMID: 21132286 DOI: 10.1007/s00253-010-3026-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 11/02/2010] [Accepted: 11/22/2010] [Indexed: 10/18/2022]
Abstract
Ribose-5-phosphate isomerase from Clostridium thermocellum converted D-psicose to D-allose, which may be useful as a pharmaceutical compound, with no by-product. The 12 active-site residues, which were obtained by molecular modeling on the basis of the solved three-dimensional structure of the enzyme, were substituted individually with Ala. Among the 12 Ala-substituted mutants, only the R132A mutant exhibited an increase in D-psicose isomerization activity. The R132E mutant showed the highest activity when the residue at position 132 was substituted with Ala, Gln, Ile, Lys, Glu, or Asp. The maximal activity of the wild-type and R132E mutant enzymes for D-psicose was observed at pH 7.5 and 80°C. The half-lives of the wild-type enzyme at 60°C, 65°C, 70°C, 75°C, and 80°C were 11, 7.0, 4.2, 1.5, and 0.6 h, respectively, whereas those of the R132E mutant enzymes were 13, 8.2, 5.1, 3.1, and 0.9 h, respectively. The specific activity and catalytic efficiency (k(cat)/K(m)) of the R132E mutant for D-psicose were 1.4- and 1.5-fold higher than those of the wild-type enzyme, respectively. When the same amount of enzyme was used, the conversion yield of D-psicose to D-allose was 32% for the R132E mutant enzyme and 25% for the wild-type enzyme after 80 min.
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Affiliation(s)
- Soo-Jin Yeom
- Department of Bioscience and Biotechnology, Konkuk University, Seoul, Republic of Korea
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9
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Terwilliger TC, Adams PD, Read RJ, McCoy AJ, Moriarty NW, Grosse-Kunstleve RW, Afonine PV, Zwart PH, Hung LW. Decision-making in structure solution using Bayesian estimates of map quality: the PHENIX AutoSol wizard. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2009; 65:582-601. [PMID: 19465773 PMCID: PMC2685735 DOI: 10.1107/s0907444909012098] [Citation(s) in RCA: 724] [Impact Index Per Article: 48.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Accepted: 03/31/2009] [Indexed: 11/13/2022]
Abstract
Ten measures of experimental electron-density-map quality are examined and the skewness of electron density is found to be the best indicator of actual map quality. A Bayesian approach to estimating map quality is developed and used in the PHENIX AutoSol wizard to make decisions during automated structure solution. Estimates of the quality of experimental maps are important in many stages of structure determination of macromolecules. Map quality is defined here as the correlation between a map and the corresponding map obtained using phases from the final refined model. Here, ten different measures of experimental map quality were examined using a set of 1359 maps calculated by re-analysis of 246 solved MAD, SAD and MIR data sets. A simple Bayesian approach to estimation of map quality from one or more measures is presented. It was found that a Bayesian estimator based on the skewness of the density values in an electron-density map is the most accurate of the ten individual Bayesian estimators of map quality examined, with a correlation between estimated and actual map quality of 0.90. A combination of the skewness of electron density with the local correlation of r.m.s. density gives a further improvement in estimating map quality, with an overall correlation coefficient of 0.92. The PHENIX AutoSol wizard carries out automated structure solution based on any combination of SAD, MAD, SIR or MIR data sets. The wizard is based on tools from the PHENIX package and uses the Bayesian estimates of map quality described here to choose the highest quality solutions after experimental phasing.
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10
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Yoon RY, Yeom SJ, Kim HJ, Oh DK. Novel substrates of a ribose-5-phosphate isomerase from Clostridium thermocellum. J Biotechnol 2009; 139:26-32. [PMID: 18984017 DOI: 10.1016/j.jbiotec.2008.09.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2008] [Revised: 09/16/2008] [Accepted: 09/23/2008] [Indexed: 10/21/2022]
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Roos AK, Mariano S, Kowalinski E, Salmon L, Mowbray SL. D-ribose-5-phosphate isomerase B from Escherichia coli is also a functional D-allose-6-phosphate isomerase, while the Mycobacterium tuberculosis enzyme is not. J Mol Biol 2008; 382:667-79. [PMID: 18640127 DOI: 10.1016/j.jmb.2008.06.090] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2008] [Revised: 06/06/2008] [Accepted: 06/17/2008] [Indexed: 11/30/2022]
Abstract
Interconversion of D-ribose-5-phosphate (R5P) and D-ribulose-5-phosphate is an important step in the pentose phosphate pathway. Two unrelated enzymes with R5P isomerase activity were first identified in Escherichia coli, RpiA and RpiB. In this organism, the essential 5-carbon sugars were thought to be processed by RpiA, while the primary role of RpiB was suggested to instead be interconversion of the rare 6-carbon sugars D-allose-6-phosphate (All6P) and D-allulose-6-phosphate. In Mycobacterium tuberculosis, where only an RpiB is found, the 5-carbon sugars are believed to be the enzyme's primary substrates. Here, we present kinetic studies examining the All6P isomerase activity of the RpiBs from these two organisms and show that only the E. coli enzyme can catalyze the reaction efficiently. All6P instead acts as an inhibitor of the M. tuberculosis enzyme in its action on R5P. X-ray studies of the M. tuberculosis enzyme co-crystallized with All6P and 5-deoxy-5-phospho-D-ribonohydroxamate (an inhibitor designed to mimic the 6-carbon sugar) and comparison with the E. coli enzyme's structure allowed us to identify differences in the active sites that explain the kinetic results. Two other structures, that of a mutant E. coli RpiB in which histidine 99 was changed to asparagine and that of wild-type M. tuberculosis enzyme, both co-crystallized with the substrate ribose-5-phosphate, shed additional light on the reaction mechanism of RpiBs generally.
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Affiliation(s)
- Annette K Roos
- Department of Cell and Molecular Biology, Biomedical Center, Uppsala University, Box 596, SE-751 24 Uppsala, Sweden
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12
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Stern A, Burgos E, Salmon L, Cazzulo J. Ribose 5-phosphate isomerase type B from Trypanosoma cruzi: kinetic properties and site-directed mutagenesis reveal information about the reaction mechanism. Biochem J 2007; 401:279-85. [PMID: 16981853 PMCID: PMC1698680 DOI: 10.1042/bj20061049] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Trypanosoma cruzi, the human parasite that causes Chagas disease, contains a functional pentose phosphate pathway, probably essential for protection against oxidative stress and also for R5P (ribose 5-phosphate) production for nucleotide synthesis. The haploid genome of the CL Brener clone of the parasite contains one gene coding for a Type B Rpi (ribose 5-phosphate isomerase), but genes encoding Type A Rpis, most frequent in eukaryotes, seem to be absent. The RpiB enzyme was expressed in Escherichia coli as a poly-His tagged active dimeric protein, which catalyses the reversible isomerization of R5P to Ru5P (ribulose 5-phosphate) with Km values of 4 mM (R5P) and 1.4 mM (Ru5P). 4-phospho-D-erythronohydroxamic acid, an analogue to the reaction intermediate when the Rpi acts via a mechanism involving the formation of a 1,2-cis-enediol, inhibited the enzyme competitively, with an IC50 value of 0.7 mM and a Ki of 1.2 mM. Site-directed mutagenesis allowed the demonstration of a role for His102, but not for His138, in the opening of the ribose furanosic ring. A major role in catalysis was confirmed for Cys69, since the C69A mutant was inactive in both forward and reverse directions of the reaction. The present paper contributes to the know-ledge of the mechanism of the Rpi reaction; in addition, the absence of RpiBs in the genomes of higher animals makes this enzyme a possible target for chemotherapy of Chagas disease.
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Affiliation(s)
- Ana L. Stern
- *Instituto de Investigaciones Biotecnologicas-Instituto Tecnologico de Chascomus (IIB-INTECH), Universidad Nacional de General San Martin-CONICET, Av General Paz 5445, INTI, edificio 24, 1650 San Martin, Buenos Aires, Argentina
| | - Emmanuel Burgos
- †Laboratoire de Chimie Bioorganique et Bioinorganique, Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO, UMR 8182), Université de Paris-Sud XI, bâtiment 420, 91405 Orsay, France
| | - Laurent Salmon
- †Laboratoire de Chimie Bioorganique et Bioinorganique, Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO, UMR 8182), Université de Paris-Sud XI, bâtiment 420, 91405 Orsay, France
| | - Juan J. Cazzulo
- *Instituto de Investigaciones Biotecnologicas-Instituto Tecnologico de Chascomus (IIB-INTECH), Universidad Nacional de General San Martin-CONICET, Av General Paz 5445, INTI, edificio 24, 1650 San Martin, Buenos Aires, Argentina
- To whom correspondence should be addressed (email )
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Conners SB, Mongodin EF, Johnson MR, Montero CI, Nelson KE, Kelly RM. Microbial biochemistry, physiology, and biotechnology of hyperthermophilic Thermotoga species. FEMS Microbiol Rev 2006; 30:872-905. [PMID: 17064285 DOI: 10.1111/j.1574-6976.2006.00039.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
High-throughput sequencing of microbial genomes has allowed the application of functional genomics methods to species lacking well-developed genetic systems. For the model hyperthermophile Thermotoga maritima, microarrays have been used in comparative genomic hybridization studies to investigate diversity among Thermotoga species. Transcriptional data have assisted in prediction of pathways for carbohydrate utilization, iron-sulfur cluster synthesis and repair, expolysaccharide formation, and quorum sensing. Structural genomics efforts aimed at the T. maritima proteome have yielded hundreds of high-resolution datasets and predicted functions for uncharacterized proteins. The information gained from genomics studies will be particularly useful for developing new biotechnology applications for T. maritima enzymes.
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Affiliation(s)
- Shannon B Conners
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA
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14
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Page R, Deacon AM, Lesley SA, Stevens RC. Shotgun crystallization strategy for structural genomics II: crystallization conditions that produce high resolution structures for T. maritima proteins. ACTA ACUST UNITED AC 2006; 6:209-17. [PMID: 16211521 DOI: 10.1007/s10969-005-1916-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2004] [Accepted: 01/16/2005] [Indexed: 11/27/2022]
Abstract
Currently, 119 high resolution structures of Thermotoga maritima proteins have been determined by the Joint Center for Structural Genomics (JCSG, www.jcsg.org). Sixty-seven of these were solved using the first implementation of the multi-tiered crystallization strategy at the JCSG for the efficient crystallization of large numbers of protein targets. Previously, we reported the analysis of all proteins crystallized using this multi-tiered strategy [Lesley, S.A. et al. (2002) Proc. Natl. Acad. Sci. USA 99, 11664-11669; Page, R. et al. (2003) Acta Crystallogr. D Biol. Crystallogr. 59, 1028-1037]. Here, we extend the analysis and describe the crystallization characteristics of those proteins that produced diffraction quality crystals, ultimately resulting in high resolution structures. First, we found that over 77% (52) of the crystals used for structure determination were produced directly from high-throughput coarse screens, indicating that less than one quarter of the crystals (15) required fine screening. In addition, as observed for the proteome screen [Page, R. et al. (2003) Acta Crystallogr. D Biol. Crystallogr. 59, 1028-1037], the majority of conditions that produced crystals for natively expressed proteins, whose structures have been determined, were distinct from those of their more extensively purified and selenomethionine-labeled counterparts. Finally, 99% of the proteins whose structures were solved crystallized in conditions contained in the JCSG Minimal Core Screen [Page, R. et al. (2003) Acta Crystallogr. D Biol. Crystallogr. 59, 1028-1037; Page, R. and Stevens, R.C. (2004) Methods 34, 373-389], a set of 67 conditions previously identified as those most likely to produce crystals of a diverse set of proteins, confirming its success for rapid identification of proteins with a natural propensity to crystallize.
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