1
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Xu S, Li ZL, Li ZM, Liu HL. Mining unique cysteine synthetases and computational study on thoroughly eliminating feedback inhibition through tunnel engineering. Protein Sci 2024; 33:e5160. [PMID: 39275998 PMCID: PMC11400630 DOI: 10.1002/pro.5160] [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: 04/11/2024] [Revised: 08/14/2024] [Accepted: 08/19/2024] [Indexed: 09/16/2024]
Abstract
L-cysteine is an essential component in pharmaceutical and agricultural industries, and synthetic biology has made strides in developing new metabolic pathways for its production, particularly in archaea with unique O-phosphoserine sulfhydrylases (OPSS) as key enzymes. In this study, we employed database mining to identify a highly catalytic activity OPSS from Acetobacterium sp. (AsOPSS). However, it was observed that the enzymatic activity of AsOPSS suffered significant feedback inhibition from the product L-cysteine, exhibiting an IC50 value of merely 1.2 mM. A semi-rational design combined with tunnel analysis strategy was conducted to engineer AsOPSS. The best variant, AsOPSSA218R was achieved, totally eliminating product inhibition without sacrificing catalytic efficiency. Molecular docking and molecular dynamic simulations indicated that the binding conformation of AsOPSSA218R with L-cys was altered, leading to a reduced affinity between L-cysteine and the active pocket. Tunnel analysis revealed that the AsOPSSA218R variant reshaped the landscape of the tunnel, resulting in the construction of a new tunnel. Furthermore, random acceleration molecular dynamics simulation and umbrella sampling simulation demonstrated that the novel tunnel improved the suitability for product release and effectively separated the interference between the product release and substrate binding processes. Finally, more than 45 mM of L-cysteine was produced in vitro within 2 h using the AsOPSSA218R variant. Our findings emphasize the potential for relieving feedback inhibition by artificially generating new product release channels, while also laying an enzymatic foundation for efficient L-cysteine production.
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Affiliation(s)
- Shuai Xu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Zong-Lin Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Zhi-Min Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
- Shanghai Collaborative Innovation Center for Biomanufacturing Technology, Shanghai, China
| | - Hong-Lai Liu
- School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, China
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2
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Identification of amino acid residues important for recognition of O-phospho-l-serine substrates by cysteine synthase. J Biosci Bioeng 2021; 131:483-490. [PMID: 33563496 DOI: 10.1016/j.jbiosc.2021.01.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 01/06/2021] [Accepted: 01/14/2021] [Indexed: 01/18/2023]
Abstract
Pyridoxal-5'-phosphate-dependent cysteine synthases synthesize l-cysteine from their primary substrates, O-acetyl-l-serine (OAS) and O-phospho-l-serine (OPS), and their secondary substrate, sulfide. The mechanism by which cysteine synthases recognize OPS remains unclear; hence, we investigated the OPS recognition mechanism of the OPS sulfhydrylase obtained from Aeropyrum pernix K1 (ApOPSS) and the OAS sulfhydrylase-B obtained from Escherichia coli (EcOASS-B), using protein engineering methods. From the amino acid sequence alignment data, we found that some OPS sulfhydrylases (OPSSs) had a Tyr corresponding to the Phe225 and Phe141 residues in ApOPSS and EcOASS-B, respectively, and that the Tyr residue could facilitate OPS recognition. The enzymatic activity of the ApOPSS F225Y mutant toward OPS decreased compared with that of the wild-type; the kcat value decreased 2.3-fold during cysteine synthesis. X-ray crystallography results of the complex of ApOPSS F225Y and F225Y/R297A mutants bound to OPS and l-cysteine showed that kcat might have decreased because of the stronger interactions of the reaction product phosphate with Tyr225, Thr203, and Arg297, and that of the l-cysteine with Tyr225. The specific activity of the EcOASS-B F141Y mutant toward OPS increased by 50-fold compared with that of the wild-type. Thus, a Tyr within a cysteine synthase corresponding to the Phe225 in ApOPSS and Phe141 in EcOASS-B could act as a key residue for classifying an unknown cysteine synthase as an OPSS. The elucidation of the substrate recognition system of cysteine synthases would enable us to effectively classify cysteine synthases and develop pathogen-specific drug targets, as OPSS is absent in mammalian hosts.
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3
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Jez JM. Structural biology of plant sulfur metabolism: from sulfate to glutathione. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:4089-4103. [PMID: 30825314 DOI: 10.1093/jxb/erz094] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 02/12/2019] [Indexed: 06/09/2023]
Abstract
Sulfur is an essential element for all organisms. Plants must assimilate this nutrient from the environment and convert it into metabolically useful forms for the biosynthesis of a wide range of compounds, including cysteine and glutathione. This review summarizes structural biology studies on the enzymes involved in plant sulfur assimilation [ATP sulfurylase, adenosine-5'-phosphate (APS) reductase, and sulfite reductase], cysteine biosynthesis (serine acetyltransferase and O-acetylserine sulfhydrylase), and glutathione biosynthesis (glutamate-cysteine ligase and glutathione synthetase) pathways. Overall, X-ray crystal structures of enzymes in these core pathways provide molecular-level information on the chemical events that allow plants to incorporate sulfur into essential metabolites and revealed new biochemical regulatory mechanisms, such as structural rearrangements, protein-protein interactions, and thiol-based redox switches, for controlling different steps in these pathways.
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Affiliation(s)
- Joseph M Jez
- Department of Biology, Washington University in St. Louis, St. Louis, MO, USA
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4
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Magalhães J, Franko N, Annunziato G, Welch M, Dolan SK, Bruno A, Mozzarelli A, Armao S, Jirgensons A, Pieroni M, Costantino G, Campanini B. Discovery of novel fragments inhibiting O-acetylserine sulphhydrylase by combining scaffold hopping and ligand-based drug design. J Enzyme Inhib Med Chem 2018; 33:1444-1452. [PMID: 30221554 PMCID: PMC6147075 DOI: 10.1080/14756366.2018.1512596] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Several bacteria rely on the reductive sulphur assimilation pathway, absent in mammals, to synthesise cysteine. Reduction of virulence and decrease in antibiotic resistance have already been associated with mutations on the genes that codify cysteine biosynthetic enzymes. Therefore, inhibition of cysteine biosynthesis has emerged as a promising strategy to find new potential agents for the treatment of bacterial infection. Following our previous efforts to explore OASS inhibition and to expand and diversify our library, a scaffold hopping approach was carried out, with the aim of identifying a novel fragment for further development. This novel chemical tool, endowed with favourable pharmacological characteristics, was successfully developed, and a preliminary Structure–Activity Relationship investigation was carried out.
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Affiliation(s)
- Joana Magalhães
- a P4T group, Department of Food and Drug , University of Parma , Parma , Italy
| | - Nina Franko
- b Laboratory of Biochemistry and Molecular Biology, Department of Food and Drug , University of Parma , Parma , Italy
| | | | - Martin Welch
- c Department of Biochemistry , Cambridge University , Cambridge , United Kingdom
| | - Stephen K Dolan
- c Department of Biochemistry , Cambridge University , Cambridge , United Kingdom
| | - Agostino Bruno
- d Experimental Therapeutics Program , IFOM - The FIRC Institute for Molecular Oncology Foundation , Milano , Italy
| | - Andrea Mozzarelli
- b Laboratory of Biochemistry and Molecular Biology, Department of Food and Drug , University of Parma , Parma , Italy.,e National Institute of Biostructures and Biosystems , Rome , Italy.,f Institute of Biophysics, CNR , Pisa , Italy
| | - Stefano Armao
- g Centro Interdipartimentale "Biopharmanet-tec", Università degli Studi di Parma , Parma , Italy
| | | | - Marco Pieroni
- a P4T group, Department of Food and Drug , University of Parma , Parma , Italy
| | - Gabriele Costantino
- a P4T group, Department of Food and Drug , University of Parma , Parma , Italy.,i Centro Interdipartimentale Misure (CIM)'G. Casnati', University of Parma , Parma , Italy
| | - Barbara Campanini
- b Laboratory of Biochemistry and Molecular Biology, Department of Food and Drug , University of Parma , Parma , Italy
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5
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Nakamura T, Kunimoto K, Yuki T, Ishikawa K. Unnatural Amino Acid Synthesis by Thermostable O-Phospho-l-serine Sulfhydrylase from Hyperthermophilic Archaeon Aeropyrum pernix K1. CHEM LETT 2017. [DOI: 10.1246/cl.170822] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Takashi Nakamura
- Laboratory of Molecular Biochemistry, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829
| | - Kohei Kunimoto
- Laboratory of Molecular Biochemistry, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829
| | - Toru Yuki
- Laboratory of Molecular Biochemistry, Nagahama Institute of Bio-Science and Technology, 1266 Tamura-cho, Nagahama, Shiga 526-0829
| | - Kazuhiko Ishikawa
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577
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6
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An archaeal ADP-dependent serine kinase involved in cysteine biosynthesis and serine metabolism. Nat Commun 2016; 7:13446. [PMID: 27857065 PMCID: PMC5120207 DOI: 10.1038/ncomms13446] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 10/05/2016] [Indexed: 01/14/2023] Open
Abstract
Routes for cysteine biosynthesis are still unknown in many archaea. Here we find that the hyperthermophilic archaeon Thermococcus kodakarensis generates cysteine from serine via O-phosphoserine, in addition to the classical route from 3-phosphoglycerate. The protein responsible for serine phosphorylation is encoded by TK0378, annotated as a chromosome partitioning protein ParB. The TK0378 protein utilizes ADP as the phosphate donor, but in contrast to previously reported ADP-dependent kinases, recognizes a non-sugar substrate. Activity is specific towards free serine, and not observed with threonine, homoserine and serine residues within a peptide. Genetic analyses suggest that TK0378 is involved in serine assimilation and clearly responsible for cysteine biosynthesis from serine. TK0378 homologs, present in Thermococcales and Desulfurococcales, are most likely not ParB proteins and constitute a group of kinases involved in serine utilization. Archaea metabolism has unique adaptations to hostile environments. Here Makino et al. describe an unusual ADP-dependent kinase that phosphorylates free serine to O-phosphoserine and participates in an additional cysteine biosynthetic pathway in the archaeon Thermococcus kodakarensis.
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7
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Takeda E, Kunimoto K, Kawai Y, Kataoka M, Ishikawa K, Nakamura T. Role of F225 in O-phosphoserine sulfhydrylase from Aeropyrum pernix K1. Extremophiles 2016; 20:733-45. [DOI: 10.1007/s00792-016-0862-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 06/26/2016] [Indexed: 10/21/2022]
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8
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Chiba Y, Makiuchi T, Jeelani G, Nozaki T. Heterogeneity of the serine synthetic pathway in Entamoeba species. Mol Biochem Parasitol 2016; 207:56-60. [PMID: 27268730 DOI: 10.1016/j.molbiopara.2016.06.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 06/01/2016] [Accepted: 06/02/2016] [Indexed: 11/18/2022]
Abstract
Phosphoserine phosphatase (PSP) catalyzes the third step of the phosphorylated serine biosynthetic pathway, and occurred multiple times in evolution, while enzymes catalyzing the first and second steps in the pathway have single respective origins. In the present study, we examined the existence of PSP among genus Entamoeba including a human enteric parasite, Entamoeba histolytica. E. histolytica as well as majority of Entamoeba species have the first and second enzymes, but lacks PSP. In contrast, a reptilian enteric parasite, Entamoeba invadens possesses canonical PSP. Thus, there are variations in the existence of the serine biosynthetic ability among Entamoeba species.
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Affiliation(s)
- Yoko Chiba
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; Department of Parasitology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Takashi Makiuchi
- Department of Parasitology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Ghulam Jeelani
- Department of Parasitology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Tomoyoshi Nozaki
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; Department of Parasitology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan.
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9
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Pieroni M, Annunziato G, Beato C, Wouters R, Benoni R, Campanini B, Pertinhez TA, Bettati S, Mozzarelli A, Costantino G. Rational Design, Synthesis, and Preliminary Structure–Activity Relationships of α-Substituted-2-Phenylcyclopropane Carboxylic Acids as Inhibitors of Salmonella typhimurium O-Acetylserine Sulfhydrylase. J Med Chem 2016; 59:2567-78. [DOI: 10.1021/acs.jmedchem.5b01775] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
| | | | | | | | | | | | | | - Stefano Bettati
- Department
of Neurosciences, University of Parma, Via Volturno, 39, 43125 Parma, Italy
- National Institute of Biostructures and Biosystems, Viale delle Medaglie d’Oro 305, 00136 Rome, Italy
| | - Andrea Mozzarelli
- National Institute of Biostructures and Biosystems, Viale delle Medaglie d’Oro 305, 00136 Rome, Italy
- Institute of Biophysics, CNR, /o
Area di Ricerca San Cataldo, Via G. Moruzzi N° 1, 56124 Pisa, Italy
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10
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Kobylarz MJ, Grigg JC, Liu Y, Lee MSF, Heinrichs DE, Murphy MEP. Deciphering the Substrate Specificity of SbnA, the Enzyme Catalyzing the First Step in Staphyloferrin B Biosynthesis. Biochemistry 2016; 55:927-39. [PMID: 26794841 PMCID: PMC5084695 DOI: 10.1021/acs.biochem.5b01045] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Staphylococcus aureus assembles the siderophore,
staphyloferrin B, from l-2,3-diaminopropionic acid (l-Dap), α-ketoglutarate, and citrate. Recently, SbnA and SbnB
were shown to produce l-Dap and α-ketoglutarate from O-phospho-l-serine (OPS) and l-glutamate.
SbnA is a pyridoxal 5′-phosphate (PLP)-dependent enzyme with
homology to O-acetyl-l-serine sulfhydrylases;
however, SbnA utilizes OPS instead of O-acetyl-l-serine (OAS), and l-glutamate serves as a nitrogen
donor instead of a sulfide. In this work, we examined how SbnA dictates
substrate specificity for OPS and l-glutamate using a combination
of X-ray crystallography, enzyme kinetics, and site-directed mutagenesis.
Analysis of SbnA crystals incubated with OPS revealed the structure
of the PLP-α-aminoacrylate intermediate. Formation of the intermediate
induced closure of the active site pocket by narrowing the channel
leading to the active site and forming a second substrate binding
pocket that likely binds l-glutamate. Three active site residues
were identified: Arg132, Tyr152, Ser185 that were essential for OPS
recognition and turnover. The Y152F/S185G SbnA double mutant was completely
inactive, and its crystal structure revealed that the mutations induced
a closed form of the enzyme in the absence of the α-aminoacrylate
intermediate. Lastly, l-cysteine was shown to be a competitive
inhibitor of SbnA by forming a nonproductive external aldimine with
the PLP cofactor. These results suggest a regulatory link between
siderophore and l-cysteine biosynthesis, revealing a potential
mechanism to reduce iron uptake under oxidative stress.
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Affiliation(s)
- Marek J Kobylarz
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia , Vancouver, British Columbia, Canada V6T 1Z3
| | - Jason C Grigg
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia , Vancouver, British Columbia, Canada V6T 1Z3
| | - Yunan Liu
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia , Vancouver, British Columbia, Canada V6T 1Z3
| | - Mathew S F Lee
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia , Vancouver, British Columbia, Canada V6T 1Z3
| | | | - Michael E P Murphy
- Department of Microbiology and Immunology, Life Sciences Institute, The University of British Columbia , Vancouver, British Columbia, Canada V6T 1Z3
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11
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Nakamura T, Asai S, Nakata K, Kunimoto K, Oguri M, Ishikawa K. Thermostability and reactivity in organic solvent of O-phospho-l-serine sulfhydrylase from hyperthermophilic archaeon Aeropyrum pernix K1. Biosci Biotechnol Biochem 2015; 79:1280-6. [DOI: 10.1080/09168451.2015.1020753] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Abstract
O-phospho-l-serine sulfhydrylase (OPSS) from archaeon Aeropyrum pernix K1 is able to synthesize l-cysteine even at 80 °C. In this article, we compared thermal stability and reactivity in organic solvent of OPSS with those of O-acetyl-l-serine sulfhydrylase B (OASS-B) from Escherichia coli. As a result, the thermostability of OPSS was much higher than that of OASS-B. Moreover, the activity of OPSS increased in the reaction mixture containing the organic solvent, such as N, N′-dimethyl formamide and 1,4-dioxane, whereas that of OASS-B gradually decreased as the content of organic solvent increased. From the crystal structural analysis, the intramolecular electrostatic interactions of N-terminal domain in OPSS seemed to be correlated with the tolerance of OPSS to high temperature and organic solvent. These results indicate that OPSS is more superior to OASS-B for the industrial production of l-cysteine and unnatural amino acids that are useful pharmaceuticals in the presence of organic solvent.
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Affiliation(s)
- Takashi Nakamura
- Faculty of Bioscience, Laboratory of Molecular Biochemistry, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
| | - Shinji Asai
- Faculty of Bioscience, Laboratory of Molecular Biochemistry, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
| | - Kaori Nakata
- Faculty of Bioscience, Laboratory of Molecular Biochemistry, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
| | - Kohei Kunimoto
- Faculty of Bioscience, Laboratory of Molecular Biochemistry, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
| | - Masateru Oguri
- Faculty of Bioscience, Laboratory of Molecular Biochemistry, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
| | - Kazuhiko Ishikawa
- National Institute of Advanced Industrial Science and Technology (AIST), Osaka, Japan
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12
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Busch F, Rajendran C, Mayans O, Löffler P, Merkl R, Sterner R. TrpB2 Enzymes are O-Phospho-l-serine Dependent Tryptophan Synthases. Biochemistry 2014; 53:6078-83. [DOI: 10.1021/bi500977y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Florian Busch
- Institute
of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Chitra Rajendran
- Institute
of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Olga Mayans
- Institute
of Integrative Biology, University of Liverpool, Crown Street, Liverpool L69 7ZB, United Kingdom
| | - Patrick Löffler
- Institute
of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Rainer Merkl
- Institute
of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Reinhard Sterner
- Institute
of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
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13
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CysK2 from Mycobacterium tuberculosis is an O-phospho-L-serine-dependent S-sulfocysteine synthase. J Bacteriol 2014; 196:3410-20. [PMID: 25022854 DOI: 10.1128/jb.01851-14] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mycobacterium tuberculosis is dependent on cysteine biosynthesis, and reduced sulfur compounds such as mycothiol synthesized from cysteine serve in first-line defense mechanisms against oxidative stress imposed by macrophages. Two biosynthetic routes to l-cysteine, each with its own specific cysteine synthase (CysK1 and CysM), have been described in M. tuberculosis, but the function of a third putative sulfhydrylase in this pathogen, CysK2, has remained elusive. We present biochemical and biophysical evidence that CysK2 is an S-sulfocysteine synthase, utilizing O-phosphoserine (OPS) and thiosulfate as substrates. The enzyme uses a mechanism via a central aminoacrylate intermediate that is similar to that of other members of this pyridoxal phosphate-dependent enzyme family. The apparent second-order rate of the first half-reaction with OPS was determined as kmax/Ks = (3.97 × 10(3)) ± 619 M(-1) s(-1), which compares well to the OPS-specific mycobacterial cysteine synthase CysM with a kmax/Ks of (1.34 × 10(3)) ± 48.2. Notably, CysK2 does not utilize thiocarboxylated CysO as a sulfur donor but accepts thiosulfate and sulfide as donor substrates. The specificity constant kcat/Km for thiosulfate is 40-fold higher than for sulfide, suggesting an annotation as S-sulfocysteine synthase. Mycobacterial CysK2 thus provides a third metabolic route to cysteine, either directly using sulfide as donor or indirectly via S-sulfocysteine. Hypothetically, S-sulfocysteine could also act as a signaling molecule triggering additional responses in redox defense in the pathogen upon exposure to reactive oxygen species during dormancy.
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14
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Spyrakis F, Singh R, Cozzini P, Campanini B, Salsi E, Felici P, Raboni S, Benedetti P, Cruciani G, Kellogg GE, Cook PF, Mozzarelli A. Isozyme-specific ligands for O-acetylserine sulfhydrylase, a novel antibiotic target. PLoS One 2013; 8:e77558. [PMID: 24167577 PMCID: PMC3805590 DOI: 10.1371/journal.pone.0077558] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 09/03/2013] [Indexed: 01/06/2023] Open
Abstract
The last step of cysteine biosynthesis in bacteria and plants is catalyzed by O-acetylserine sulfhydrylase. In bacteria, two isozymes, O-acetylserine sulfhydrylase-A and O-acetylserine sulfhydrylase-B, have been identified that share similar binding sites, although the respective specific functions are still debated. O-acetylserine sulfhydrylase plays a key role in the adaptation of bacteria to the host environment, in the defense mechanisms to oxidative stress and in antibiotic resistance. Because mammals synthesize cysteine from methionine and lack O-acetylserine sulfhydrylase, the enzyme is a potential target for antimicrobials. With this aim, we first identified potential inhibitors of the two isozymes via a ligand- and structure-based in silico screening of a subset of the ZINC library using FLAP. The binding affinities of the most promising candidates were measured in vitro on purified O-acetylserine sulfhydrylase-A and O-acetylserine sulfhydrylase-B from Salmonella typhimurium by a direct method that exploits the change in the cofactor fluorescence. Two molecules were identified with dissociation constants of 3.7 and 33 µM for O-acetylserine sulfhydrylase-A and O-acetylserine sulfhydrylase-B, respectively. Because GRID analysis of the two isoenzymes indicates the presence of a few common pharmacophoric features, cross binding titrations were carried out. It was found that the best binder for O-acetylserine sulfhydrylase-B exhibits a dissociation constant of 29 µM for O-acetylserine sulfhydrylase-A, thus displaying a limited selectivity, whereas the best binder for O-acetylserine sulfhydrylase-A exhibits a dissociation constant of 50 µM for O-acetylserine sulfhydrylase-B and is thus 8-fold selective towards the former isozyme. Therefore, isoform-specific and isoform-independent ligands allow to either selectively target the isozyme that predominantly supports bacteria during infection and long-term survival or to completely block bacterial cysteine biosynthesis.
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Affiliation(s)
| | - Ratna Singh
- Department of Pharmacy, University of Parma, Parma, Italy
| | - Pietro Cozzini
- Department of Food Sciences, University of Parma, Parma, Italy
- National Institute of Biostructures and Biosystems, Rome, Italy
| | - Barbara Campanini
- Department of Pharmacy, University of Parma, Parma, Italy
- * E-mail: (BC); (AM)
| | - Enea Salsi
- Department of Pharmacy, University of Parma, Parma, Italy
| | - Paolo Felici
- Department of Pharmacy, University of Parma, Parma, Italy
| | - Samanta Raboni
- Department of Pharmacy, University of Parma, Parma, Italy
| | | | | | - Glen E. Kellogg
- Department of Medicinal Chemistry and Institute for Structural Biology and Drug Discovery, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Paul F. Cook
- Department of Biochemistry, University of Oklahoma, Norman, Oklahoma, United States of America
| | - Andrea Mozzarelli
- Department of Pharmacy, University of Parma, Parma, Italy
- National Institute of Biostructures and Biosystems, Rome, Italy
- * E-mail: (BC); (AM)
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15
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The cysteine regulatory complex from plants and microbes: what was old is new again. Curr Opin Struct Biol 2013; 23:302-10. [DOI: 10.1016/j.sbi.2013.02.011] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 01/16/2013] [Accepted: 02/26/2013] [Indexed: 11/20/2022]
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16
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Spyrakis F, Felici P, Bayden AS, Salsi E, Miggiano R, Kellogg GE, Cozzini P, Cook PF, Mozzarelli A, Campanini B. Fine tuning of the active site modulates specificity in the interaction of O-acetylserine sulfhydrylase isozymes with serine acetyltransferase. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:169-81. [DOI: 10.1016/j.bbapap.2012.09.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 09/10/2012] [Accepted: 09/12/2012] [Indexed: 10/27/2022]
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Nakamura T, Kawai Y, Kunimoto K, Iwasaki Y, Nishii K, Kataoka M, Ishikawa K. Structural Analysis of the Substrate Recognition Mechanism in O-Phosphoserine Sulfhydrylase from the Hyperthermophilic Archaeon Aeropyrum pernix K1. J Mol Biol 2012; 422:33-44. [DOI: 10.1016/j.jmb.2012.05.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 04/26/2012] [Accepted: 05/04/2012] [Indexed: 10/28/2022]
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18
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Abstract
Studies on sulfur metabolism in archaea have revealed many novel enzymes and pathways and have advanced our understanding on metabolic processes, not only of the archaea, but of biology in general. A variety of dissimilatory sulfur metabolisms, i.e. reactions used for energy conservation, are found in archaea from both the Crenarchaeota and Euryarchaeota phyla. Although not yet fully characterized, major processes include aerobic elemental sulfur (S(0)) oxidation, anaerobic S(0) reduction, anaerobic sulfate/sulfite reduction and anaerobic respiration of organic sulfur. Assimilatory sulfur metabolism, i.e. reactions used for biosynthesis of sulfur-containing compounds, also possesses some novel features. Cysteine biosynthesis in some archaea uses a unique tRNA-dependent pathway. Fe-S cluster biogenesis in many archaea differs from that in bacteria and eukaryotes and requires unidentified components. The eukaryotic ubiquitin system is conserved in archaea and involved in both protein degradation and biosynthesis of sulfur-containing cofactors. Lastly, specific pathways are utilized for the biosynthesis of coenzyme M and coenzyme B, the sulfur-containing cofactors required for methanogenesis.
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Affiliation(s)
- Yuchen Liu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
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Mozzarelli A, Bettati S, Campanini B, Salsi E, Raboni S, Singh R, Spyrakis F, Kumar VP, Cook PF. The multifaceted pyridoxal 5'-phosphate-dependent O-acetylserine sulfhydrylase. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1814:1497-510. [PMID: 21549222 DOI: 10.1016/j.bbapap.2011.04.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2011] [Revised: 04/17/2011] [Accepted: 04/20/2011] [Indexed: 12/14/2022]
Abstract
Cysteine is the final product of the reductive sulfate assimilation pathway in bacteria and plants and serves as the precursor for all sulfur-containing biological compounds, such as methionine, S-adenosyl methionine, iron-sulfur clusters and glutathione. Moreover, in several microorganisms cysteine plays a role as a reducing agent, eventually counteracting host oxidative defense strategies. Cysteine is synthesized by the PLP-dependent O-acetylserine sulfhydrylase, a dimeric enzyme belonging to the fold type II, catalyzing a beta-replacement reaction. In this review, the spectroscopic properties, catalytic mechanism, three-dimensional structure, conformational changes accompanying catalysis, determinants of enzyme stability, role of selected amino acids in catalysis, and the regulation of enzyme activity by ligands and interaction with serine acetyltransferase, the preceding enzyme in the biosynthetic pathway, are described. Given the key biological role played by O-acetylserine sulfhydrylase in bacteria, inhibitors with potential antibiotic activity have been developed. This article is part of a Special Issue entitled: Pyridoxal Phospate Enzymology.
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Affiliation(s)
- Andrea Mozzarelli
- Department of Biochemistry and Molecular Biology, University of Parma, Parma, Italy
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20
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Ishikawa K, Mino K, Nakamura T. New function and application of the cysteine synthase from archaea. Biochem Eng J 2010. [DOI: 10.1016/j.bej.2009.10.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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21
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Convergent evolution of coenzyme M biosynthesis in the Methanosarcinales: cysteate synthase evolved from an ancestral threonine synthase. Biochem J 2009; 424:467-78. [PMID: 19761441 DOI: 10.1042/bj20090999] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The euryarchaeon Methanosarcina acetivorans has no homologues of the first three enzymes that produce the essential methanogenic coenzyme M (2-mercaptoethanesulfonate) in Methanocaldococcus jannaschii. A single M. acetivorans gene was heterologously expressed to produce a functional sulfopyruvate decarboxylase protein, the fourth canonical enzyme in this biosynthetic pathway. An adjacent gene, at locus MA3297, encodes one of the organism's two threonine synthase homologues. When both paralogues from this organism were expressed in an Escherichia coli threonine synthase mutant, the MA1610 gene complemented the thrC mutation, whereas the MA3297 gene did not. Both PLP (pyridoxal 5'-phosphate)-dependent proteins were heterologously expressed and purified, but only the MA1610 protein catalysed the canonical threonine synthase reaction. The MA3297 protein specifically catalysed a new beta-replacement reaction that converted L-phosphoserine and sulfite into L-cysteate and inorganic phosphate. This oxygen-independent mode of sulfonate biosynthesis exploits the facile nucleophilic addition of sulfite to an alpha,beta-unsaturated intermediate (PLP-bound dehydroalanine). An amino acid sequence comparison indicates that cysteate synthase evolved from an ancestral threonine synthase through gene duplication, and the remodelling of active site loop regions by amino acid insertion and substitutions. The cysteate product can be converted into sulfopyruvate by an aspartate aminotransferase enzyme, establishing a new convergent pathway for coenzyme M biosynthesis that appears to function in members of the orders Methanosarcinales and Methanomicrobiales. These differences in coenzyme M biosynthesis afford the opportunity to develop methanogen inhibitors that discriminate between the classes of methanogenic archaea.
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Abstract
Genome mining and biochemical analyses have shown that Leishmania major possesses two pathways for cysteine synthesis – the de novo biosynthesis pathway comprising SAT (serine acetyltransferase) and CS (cysteine synthase) and the RTS (reverse trans-sulfuration) pathway comprising CBS (cystathionine β-synthase) and CGL (cystathionine γ-lyase). The LmjCS (L. major CS) is similar to the type A CSs of bacteria and catalyses the synthesis of cysteine using O-acetylserine and sulfide with Kms of 17.5 and 0.13 mM respectively. LmjCS can use sulfide provided by the action of MST (mercaptopyruvate sulfurtransferase) on 3-MP (3-mercaptopyruvate). LmjCS forms a bi-enzyme complex with Leishmania SAT (and Arabidopsis SAT), with residues Lys222, His226 and Lys227 of LmjCS being involved in the complex formation. LmjCBS (L. major CBS) catalyses the synthesis of cystathionine from homocysteine, but, unlike mammalian CBS, also has high cysteine synthase activity (but with the Km for sulfide being 10.7 mM). In contrast, LmjCS does not have CBS activity. CS was up-regulated when promastigotes were grown in medium with limited availability of sulfur amino acids. Exogenous methionine stimulated growth under these conditions and also the levels of intracellular cysteine, glutathione and trypanothione, whereas cysteine had no effect on growth or the intracellular cysteine levels, correlating with the low rate of transport of cysteine into the cell. These results suggest that cysteine is generated endogenously by promastigotes of Leishmania. The absence of CS from mammals and the clear differences between CBS of mammals and Leishmania suggest that each of the parasite enzymes could be a viable drug target.
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Ågren D, Schnell R, Oehlmann W, Singh M, Schneider G. Cysteine Synthase (CysM) of Mycobacterium tuberculosis Is an O-Phosphoserine Sulfhydrylase. J Biol Chem 2008; 283:31567-74. [DOI: 10.1074/jbc.m804877200] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Covarrubias AS, Högbom M, Bergfors T, Carroll P, Mannerstedt K, Oscarson S, Parish T, Jones TA, Mowbray SL. Structural, Biochemical, and In Vivo Investigations of the Threonine Synthase from Mycobacterium tuberculosis. J Mol Biol 2008; 381:622-33. [DOI: 10.1016/j.jmb.2008.05.086] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Revised: 05/28/2008] [Accepted: 05/30/2008] [Indexed: 11/25/2022]
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25
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Hauenstein SI, Perona JJ. Redundant synthesis of cysteinyl-tRNACys in Methanosarcina mazei. J Biol Chem 2008; 283:22007-17. [PMID: 18559341 PMCID: PMC2494925 DOI: 10.1074/jbc.m801839200] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2008] [Revised: 05/19/2008] [Indexed: 11/06/2022] Open
Abstract
A subset of methanogenic archaea synthesize the cysteinyl-tRNA(Cys) (Cys-tRNA(Cys)) needed for protein synthesis using both a canonical cysteinyl-tRNA synthetase (CysRS) as well as a set of two enzymes that operate via a separate indirect pathway. In the indirect route, phosphoseryl-tRNA(Cys) (Sep-tRNA(Cys)) is first synthesized by phosphoseryl-tRNA synthetase (SepRS), and this misacylated intermediate is then converted to Cys-tRNA(Cys) by Sep-tRNA:Cys-tRNA synthase (SepCysS) via a pyridoxal phosphate-dependent mechanism. Here, we explore the function of all three enzymes in the mesophilic methanogen Methanosarcina mazei. The genome of M. mazei also features three distinct tRNA(Cys) isoacceptors, further indicating the unusual and complex nature of Cys-tRNA(Cys) synthesis in this organism. Comparative aminoacylation kinetics by M. mazei CysRS and SepRS reveals that each enzyme prefers a distinct tRNA(Cys) isoacceptor or pair of isoacceptors. Recognition determinants distinguishing the tRNAs are shown to reside in the globular core of the molecule. Both enzymes also require the S-adenosylmethione-dependent formation of (m1)G37 in the anticodon loop for efficient aminoacylation. We further report a new, highly sensitive assay to measure the activity of SepCysS under anaerobic conditions. With this approach, we demonstrate that SepCysS functions as a multiple-turnover catalyst with kinetic behavior similar to bacterial selenocysteine synthase and the archaeal/eukaryotic SepSecS enzyme. Together, these data suggest that both metabolic routes and all three tRNA(Cys) species in M. mazei play important roles in the cellular physiology of the organism.
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Affiliation(s)
- Scott I Hauenstein
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106-9510, USA
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A catalytic mechanism that explains a low catalytic activity of serine dehydratase like-1 from human cancer cells: Crystal structure and site-directed mutagenesis studies. Biochim Biophys Acta Gen Subj 2008; 1780:809-18. [DOI: 10.1016/j.bbagen.2008.01.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2007] [Revised: 01/29/2008] [Accepted: 01/30/2008] [Indexed: 11/23/2022]
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Genome sequence of Thermofilum pendens reveals an exceptional loss of biosynthetic pathways without genome reduction. J Bacteriol 2008; 190:2957-65. [PMID: 18263724 DOI: 10.1128/jb.01949-07] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We report the complete genome of Thermofilum pendens, a deeply branching, hyperthermophilic member of the order Thermoproteales in the archaeal kingdom Crenarchaeota. T. pendens is a sulfur-dependent, anaerobic heterotroph isolated from a solfatara in Iceland. It is an extracellular commensal, requiring an extract of Thermoproteus tenax for growth, and the genome sequence reveals that biosynthetic pathways for purines, most amino acids, and most cofactors are absent. In fact, T. pendens has fewer biosynthetic enzymes than obligate intracellular parasites, although it does not display other features that are common among obligate parasites and thus does not appear to be in the process of becoming a parasite. It appears that T. pendens has adapted to life in an environment rich in nutrients. T. pendens was known previously to utilize peptides as an energy source, but the genome revealed a substantial ability to grow on carbohydrates. T. pendens is the first crenarchaeote and only the second archaeon found to have a transporter of the phosphotransferase system. In addition to fermentation, T. pendens may obtain energy from sulfur reduction with hydrogen and formate as electron donors. It may also be capable of sulfur-independent growth on formate with formate hydrogen lyase. Additional novel features are the presence of a monomethylamine:corrinoid methyltransferase, the first time that this enzyme has been found outside the Methanosarcinales, and the presence of a presenilin-related protein. The predicted highly expressed proteins do not include proteins encoded by housekeeping genes and instead include ABC transporters for carbohydrates and peptides and clustered regularly interspaced short palindromic repeat-associated proteins.
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Klipcan L, Frenkel-Morgenstern M, Safro MG. Presence of tRNA-dependent pathways correlates with high cysteine content in methanogenic Archaea. Trends Genet 2008; 24:59-63. [DOI: 10.1016/j.tig.2007.11.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2007] [Revised: 11/02/2007] [Accepted: 11/21/2007] [Indexed: 10/22/2022]
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Westrop GD, Goodall G, Mottram JC, Coombs GH. Cysteine biosynthesis in Trichomonas vaginalis involves cysteine synthase utilizing O-phosphoserine. J Biol Chem 2006; 281:25062-75. [PMID: 16735516 PMCID: PMC2645516 DOI: 10.1074/jbc.m600688200] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Trichomonas vaginalis is an early divergent eukaryote with many unusual biochemical features. It is an anaerobic protozoan parasite of humans that is thought to rely heavily on cysteine as a major redox buffer, because it lacks glutathione. We report here that for synthesis of cysteine from sulfide, T. vaginalis relies upon cysteine synthase. The enzyme (TvCS1) can use either O-acetylserine or O-phosphoserine as substrates. The K(m) values of the enzyme for sulfide are very low (0.02 mm), suggesting that the enzyme may be a means of ensuring that sulfide in the parasite is maintained at a low level. T. vaginalis appears to lack serine acetyltransferase, the source of O-acetylserine in many cells, but has a functional 3-phosphoglycerate dehydrogenase and an O-phosphoserine aminotransferase that together result in the production of O-phosphoserine, suggesting that this is the physiological substrate. TvCS1 can also use thiosulfate as substrate. Overall, TvCS1 has substrate specificities similar to those reported for cysteine synthases of Aeropyrum pernix and Escherichia coli, and this is reflected by sequence similarities around the active site. We suggest that these enzymes are classified together as type B cysteine synthases, and we hypothesize that the use of O-phosphoserine is a common characteristic of these cysteine synthases. The level of cysteine synthase in T. vaginalis is regulated according to need, such that parasites growing in an environment rich in cysteine have low activity, whereas exposure to propargylglycine results in elevated cysteine synthase activity. Humans lack cysteine synthase; therefore, this parasite enzyme could be an exploitable drug target.
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Affiliation(s)
| | | | | | - Graham H. Coombs
- To whom all correspondence should be addressed at: Division of Infection & Immunity, University of Glasgow, Glasgow Biomedical Research Centre, Glasgow G12 8TA, UK. Tel: +44 141 330 4777; Fax: +44 141 330 3516; e-mail:
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