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Peng M, Zhao S, Hu Y, Zhang L, Zhou T, Wu M, Xu M, Jiang K, Huang Y, Li D, Lun ZR, Wu Z, Shen J. Nitric oxide-induced endoplasmic reticulum stress of Schistosoma japonicum inhibits the worm development in rats. Free Radic Biol Med 2024; 212:295-308. [PMID: 38141890 DOI: 10.1016/j.freeradbiomed.2023.12.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 12/12/2023] [Accepted: 12/20/2023] [Indexed: 12/25/2023]
Abstract
Schistosomiasis, caused by Schistosoma spp., is a zoonotic parasitic disease affecting human health. Rattus norvegicus (rats) are a non-permissive host of Schistosoma, in which the worms cannot mature and cause typical egg granuloma. We previously demonstrated that inherent high levels of nitric oxide (NO), produced by inducible NO synthase (iNOS), is a key molecule in blocking the development of S. japonicum in rats. To further explore the mechanism of NO inhibiting S. japonicum development in rats, we performed S-nitrosocysteine proteomics of S. japonicum collected from infected rats and mice. The results suggested that S. japonicum in rats may have undergone endoplasmic reticulum (ER) stress. Interestingly, we found that the ER of S. japonicum in rats showed marked damage, while the ER of the worm in iNOS-/- rats and mice were relatively normal. Moreover, the expression of ER stress markers in S. japonicum from WT rats was significantly increased, compared with S. japonicum from iNOS-/- rats and mice. Using the NO donor sodium nitroprusside in vitro, we demonstrated that NO could induce ER stress in S. japonicum in a dose-dependent manner, and the NO-induced ER stress in S. japonicum could be inhibited by ER stress inhibitor 4-Phenyl butyric acid. We further verified that inhibiting ER stress of S. japonicum in rats promoted parasite development and survival. Furthermore, we demonstrated that NO-induced ER stress of S. japonicum was related to the efflux of Ca2+ from ER and the impairment of mitochondrial function. Collectively, these findings show that high levels of NO in rats could induce ER stress in S. japonicum by promoting the efflux of Ca2+ from ER and damaging the mitochondrial function, which block the worm development. Thus, this study further clarifies the mechanism of anti-schistosome in rats and provides potential strategies for drug development against schistosomiasis and other parasitosis.
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Affiliation(s)
- Mei Peng
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China; Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China; Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, China; Department of Laboratory Medicine, The Eighth Affiliated Hospital, Sun Yat-Sen University, Shenzhen, 518000, China
| | - Siyu Zhao
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China; Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China; Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, China
| | - Yunyi Hu
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China; Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China; Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, China
| | - Lichao Zhang
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China; Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China; Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, China
| | - Tao Zhou
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China; Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China; Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, China
| | - Mingrou Wu
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China; Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China; Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, China
| | - Meiyining Xu
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China; Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China; Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, China
| | - Kefeng Jiang
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China; Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China; Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, China
| | - Yun Huang
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China; Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China; Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, China
| | - Dinghao Li
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China; Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China; Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, China
| | - Zhao-Rong Lun
- Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China; State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Zhongdao Wu
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China; Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China; Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, China
| | - Jia Shen
- Department of Parasitology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, 510080, China; Key Laboratory of Tropical Disease Control of the Ministry of Education, Sun Yat-Sen University, Guangzhou, 510080, China; Provincial Engineering Technology Research Center for Biological Vector Control, Guangzhou, 510080, China.
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Karthika A, Hemavathy N, Amala M, Rajamanikandan S, Veerapandian M, Prabhu D, Vetrivel U, Jung Chen C, Jeyaraj Pandian C, Jeyakanthan J. Structural and functional characterization of 6-phosphogluconate dehydrogenase in Plasmodium falciparum (3D7) and identification of its potent inhibitors. J Biomol Struct Dyn 2024; 42:2058-2074. [PMID: 37599457 DOI: 10.1080/07391102.2023.2248271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 04/09/2023] [Indexed: 08/22/2023]
Abstract
The malarial parasite Plasmodium falciparum predominantly causes severe malaria and deaths worldwide. Moreover, resistance developed by P. falciparum to frontline drugs in recent years has markedly increased malaria-related deaths in South Asian Countries. Ribulose 5-phosphate and NADPH synthesized by Pentose Phosphate Pathway (PPP) act as a direct precursor for nucleotide synthesis and P. falciparum survival during oxidative challenges in the intra-erythrocytic growth phase . In the present study, we have elucidated the structure and functional characteristics of 6-phosphogluconate dehydrogenase (6PGD) in P. falciparum and have identified potent hits against 6PGD by pharmacophore-based virtual screening with ZINC and ChemBridge databases. Molecular docking and Molecular dynamics simulation, binding free energies (MMGBSA & MMPBSA), and Density Functional Theory (DFT) calculations were integratively employed to validate and prioritize the most potential hits. The 6PGD structure was found to have an open and closed conformation during MD simulation. The apo form of 6PGD was found to be in closed conformation, while a open conformation attributed to facilitating binding of cofactor. It was also inferred from the conformational analysis that the small domain of 6PGD has a high influence in altering the conformation that may aid in open/closed conformation of 6PGD. The top three hits identified using pharmacophore hypotheses were ChemBridge_11084819, ChemBridge_80178394, and ChemBridge_17912340. Though all three hits scored a high glide score, MMGBSA, and favorable ADMET properties, ChemBridge_11084819 and ChemBrdige_17912340 showed higher stability and binding free energy. Moreover, these hits also featured stable H-bond interactions with the active loop of 6PGD with binding free energy comparable to substrate-bound complex. Therefore, the ChemBridge_11084819 and ChemBridge_17912340 moieties demonstrate to have high therapeutic potential against 6PGD in P. falciparum.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Alagesan Karthika
- Structural Biology and Bio-Computing Lab, Department of Bioinformatics, Science Block, Alagappa University, Karaikudi, Tamil Nadu, India
| | - Nagarajan Hemavathy
- Structural Biology and Bio-Computing Lab, Department of Bioinformatics, Science Block, Alagappa University, Karaikudi, Tamil Nadu, India
- Centre for Bioinformatics, Vision Research Foundation, Chennai, Tamil Nadu, India
| | - Mathimaran Amala
- Structural Biology and Bio-Computing Lab, Department of Bioinformatics, Science Block, Alagappa University, Karaikudi, Tamil Nadu, India
| | - Sundaraj Rajamanikandan
- Centre for Drug Discovery, Karpagam Academy of Higher Education, Coimbatore, Tamil Nadu, India
| | - Malaisamy Veerapandian
- Structural Biology and Bio-Computing Lab, Department of Bioinformatics, Science Block, Alagappa University, Karaikudi, Tamil Nadu, India
| | - Dhamodharan Prabhu
- Centre for Drug Discovery, Karpagam Academy of Higher Education, Coimbatore, Tamil Nadu, India
| | - Umashankar Vetrivel
- ICMR-National Institute of Traditional Medicine, Nehru Nagar, Belagavi, Karnataka, India
- ICMR-National Institute for Research in Tuberculosis, Chennai, Tamil Nadu, India
| | - Chun Jung Chen
- Life Science Group, Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu, Taiwan
| | - Chitra Jeyaraj Pandian
- Department of Biotechnology, Dr. Umayal Ramanathan College for Women, Karaikudi, Tamil Nadu, India
| | - Jeyaraman Jeyakanthan
- Structural Biology and Bio-Computing Lab, Department of Bioinformatics, Science Block, Alagappa University, Karaikudi, Tamil Nadu, India
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Pawłowska M, Mila-Kierzenkowska C, Szczegielniak J, Woźniak A. Oxidative Stress in Parasitic Diseases-Reactive Oxygen Species as Mediators of Interactions between the Host and the Parasites. Antioxidants (Basel) 2023; 13:38. [PMID: 38247462 PMCID: PMC10812656 DOI: 10.3390/antiox13010038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 12/20/2023] [Accepted: 12/22/2023] [Indexed: 01/23/2024] Open
Abstract
Oxidative stress plays a significant role in the development and course of parasitic infections, both in the attacked host organism and the parasite organism struggling to survive. The host uses large amounts of reactive oxygen species (ROS), mainly superoxide anion (O2•-) and hydrogen peroxide (H2O2), to fight the developing parasitic disease. On the other hand, the parasite develops the most effective defense mechanisms and resistance to the effects of ROS and strives to survive in the host organism it has colonized, using the resources and living environment available for its development and causing the host's weakening. The paper reviews the literature on the role of oxidative stress in parasitic diseases, which are the most critical epidemiological problem worldwide. The most common parasitosis in the world is malaria, with 300-500 million new cases and about 1 million deaths reported annually. In Europe and Poland, the essential problem is intestinal parasites. Due to a parasitic infection, the concentration of antioxidants in the host decreases, and the concentration of products of cellular components oxidation increases. In response to the increased number of reactive oxygen species attacking it, the parasites have developed effective defense mechanisms, including primarily the action of antioxidant enzymes, especially superoxide dismutase and nicotinamide adenine dinucleotide phosphate hydrogen (NADPH)-dependent complexes glutathione and thioredoxin.
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Affiliation(s)
- Marta Pawłowska
- Department of Medical Biology and Biochemistry, Faculty of Medicine, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-092 Bydgoszcz, Poland; (C.M.-K.); (A.W.)
| | - Celestyna Mila-Kierzenkowska
- Department of Medical Biology and Biochemistry, Faculty of Medicine, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-092 Bydgoszcz, Poland; (C.M.-K.); (A.W.)
| | - Jan Szczegielniak
- Physiotherapy Department, Faculty of Physical Education and Physiotherapy, Opole University of Technology, 45-758 Opole, Poland;
- Ministry of Internal Affairs and Administration’s Specialist Hospital of St. John Paul II, 48-340 Glucholazy, Poland
| | - Alina Woźniak
- Department of Medical Biology and Biochemistry, Faculty of Medicine, Ludwik Rydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-092 Bydgoszcz, Poland; (C.M.-K.); (A.W.)
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4
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Yu H, Hong J, Seok J, Seu YB, Kim IK, Kim KJ. Crystal Structures of 6-Phosphogluconate Dehydrogenase from Corynebacterium glutamicum. J Microbiol Biotechnol 2023; 33:1361-1369. [PMID: 37417004 PMCID: PMC10619557 DOI: 10.4014/jmb.2305.05002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 06/11/2023] [Accepted: 06/16/2023] [Indexed: 07/08/2023]
Abstract
Corynebacterium glutamicum (C. glutamicum) has been considered a very important and meaningful industrial microorganism for the production of amino acids worldwide. To produce amino acids, cells require nicotinamide adenine dinucleotide phosphate (NADPH), which is a biological reducing agent. The pentose phosphate pathway (PPP) can supply NADPH in cells via the 6-phosphogluconate dehydrogenase (6PGD) enzyme, which is an oxidoreductase that converts 6-phosphogluconate (6PG) to ribulose 5-phosphate (Ru5P), to produce NADPH. In this study, we identified the crystal structure of 6PGD_apo and 6PGD_NADP from C. glutamicum ATCC 13032 (Cg6PGD) and reported our biological research based on this structure. We identified the substrate binding site and co-factor binding site of Cg6PGD, which are crucial for understanding this enzyme. Based on the findings of our research, Cg6PGD is expected to be used as a NADPH resource in the food industry and as a drug target in the pharmaceutical industry.
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Affiliation(s)
- Hyeonjeong Yu
- School of Life Sciences, BK21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Jiyeon Hong
- KNU Institute for Microorganisms, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Jihye Seok
- School of Life Sciences, BK21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Young-Bae Seu
- School of Life Sciences, BK21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu 41566, Republic of Korea
- KNU Institute for Microorganisms, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Il-Kwon Kim
- KNU Institute for Microorganisms, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Kyung-Jin Kim
- School of Life Sciences, BK21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu 41566, Republic of Korea
- KNU Institute for Microorganisms, Kyungpook National University, Daegu 41566, Republic of Korea
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Berneburg I, Stumpf M, Velten AS, Rahlfs S, Przyborski J, Becker K, Fritz-Wolf K. Structure of Leishmania donovani 6-Phosphogluconate Dehydrogenase and Inhibition by Phosphine Gold(I) Complexes: A Potential Approach to Leishmaniasis Treatment. Int J Mol Sci 2023; 24:ijms24108615. [PMID: 37239962 DOI: 10.3390/ijms24108615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
As unicellular parasites are highly dependent on NADPH as a source for reducing equivalents, the main NADPH-producing enzymes glucose 6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) of the pentose phosphate pathway are considered promising antitrypanosomatid drug targets. Here we present the biochemical characterization and crystal structure of Leishmania donovani 6PGD (Ld6PGD) in complex with NADP(H). Most interestingly, a previously unknown conformation of NADPH is visible in this structure. In addition, we identified auranofin and other gold(I)-containing compounds as efficient Ld6PGD inhibitors, although it has so far been assumed that trypanothione reductase is the sole target of auranofin in Kinetoplastida. Interestingly, 6PGD from Plasmodium falciparum is also inhibited at lower micromolar concentrations, whereas human 6PGD is not. Mode-of-inhibition studies indicate that auranofin competes with 6PG for its binding site followed by a rapid irreversible inhibition. By analogy with other enzymes, this suggests that the gold moiety is responsible for the observed inhibition. Taken together, we identified gold(I)-containing compounds as an interesting class of inhibitors against 6PGDs from Leishmania and possibly from other protozoan parasites. Together with the three-dimensional crystal structure, this provides a valid basis for further drug discovery approaches.
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Affiliation(s)
- Isabell Berneburg
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
| | - Michaela Stumpf
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
| | - Ann-Sophie Velten
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
| | - Stefan Rahlfs
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
| | - Jude Przyborski
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
| | - Katja Becker
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
| | - Karin Fritz-Wolf
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, 35392 Giessen, Germany
- Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
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Hanau S, Helliwell JR. 6-Phosphogluconate dehydrogenase and its crystal structures. Acta Crystallogr F Struct Biol Commun 2022; 78:96-112. [PMID: 35234135 PMCID: PMC8900737 DOI: 10.1107/s2053230x22001091] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 01/31/2022] [Indexed: 11/10/2022] Open
Abstract
6-Phosphogluconate dehydrogenase (6PGDH; EC 1.1.1.44) catalyses the oxidative decarboxylation of 6-phosphogluconate to ribulose 5-phosphate in the context of the oxidative part of the pentose phosphate pathway. Depending on the species, it can be a homodimer or a homotetramer. Oligomerization plays a functional role not only because the active site is at the interface between subunits but also due to the interlocking tail-modulating activity, similar to that of isocitrate dehydrogenase and malic enzyme, which catalyse a similar type of reaction. Since the pioneering crystal structure of sheep liver 6PGDH, which allowed motifs common to the β-hydroxyacid dehydrogenase superfamily to be recognized, several other 6PGDH crystal structures have been solved, including those of ternary complexes. These showed that more than one conformation exists, as had been suggested for many years from enzyme studies in solution. It is inferred that an asymmetrical conformation with a rearrangement of one of the two subunits underlies the homotropic cooperativity. There has been particular interest in the presence or absence of sulfate during crystallization. This might be related to the fact that this ion, which is a competitive inhibitor that binds in the active site, can induce the same 6PGDH configuration as in the complexes with physiological ligands. Mutagenesis, inhibitors, kinetic and binding studies, post-translational modifications and research on the enzyme in cancer cells have been complementary to the crystallographic studies. Computational modelling and new structural studies will probably help to refine the understanding of the functioning of this enzyme, which represents a promising therapeutic target in immunity, cancer and infective diseases. 6PGDH also has applied-science potential as a biosensor or a biobattery. To this end, the enzyme has been efficiently immobilized on specific polymers and nanoparticles. This review spans the 6PGDH literature and all of the 6PGDH crystal structure data files held by the Protein Data Bank.
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Jakkula P, Narsimulu B, Qureshi IA. Biochemical and structural insights into 6-phosphogluconate dehydrogenase from Leishmania donovani. Appl Microbiol Biotechnol 2021; 105:5471-5489. [PMID: 34250571 DOI: 10.1007/s00253-021-11434-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 05/19/2021] [Accepted: 06/13/2021] [Indexed: 11/29/2022]
Abstract
6-phosphogluconate dehydrogenase (6PGDH) participates in pentose phosphate pathway of glucose metabolism by catalyzing oxidative decarboxylation of 6-phsophogluconate (6PG) and its absence has been lethal for several eukaryotes. Despite being a validated drug target in many organisms like Plasmodium, the enzyme has not been explored in leishmanial parasites. In the present study, 6PGDH of Leishmania donovani (Ld6PGDH) is cloned and purified followed by its characterization using biochemical and structural approaches. Ld6PGDH lacks the glycine-serine-rich sequence at its C-terminal that is present in other eukaryotes including humans. Leishmanial 6PGDH possesses more affinity for substrate (6PG) and cofactor (NADP) in comparison to that of human. The enzymatic activity is inhibited by gentamicin and cefuroxime through competitive mode with functioning more potently towards leishmanial 6PGDH than its human counterpart. CD analysis has shown higher α-helical content in the secondary structure of Ld6PGDH, while fluorescence studies revealed that tryptophan residues are not completely accessible to solvent environment. The three-dimensional structure was generated through homology modelling and docked with substrate and cofactor. The docking studies demonstrated two separate binding pockets for 6PG and NADP with higher affinity for the cofactor binding, and Asn105 is interacting with substrate as well as the cofactor. Additionally, MD simulation has shown complexes of Ld6PGDH with 6PG and NADP to be more stable than its apo form. Altogether, the present study might provide the foundation to investigate this enzyme as potential target against leishmaniasis. KEY POINTS: • Ld6PGDH enzymatic activity is competitively inhibited by gentamicin and cefuroxime. • It displays more helical contents and all structural characteristics of 6PGDH family. • Interaction studies demonstrate higher affinity of cofactor than substrate for Ld6PGDH.
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Affiliation(s)
- Pranay Jakkula
- Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Prof. C.R. Rao Road, Hyderabad, 500046, India
| | - Bandigi Narsimulu
- Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Prof. C.R. Rao Road, Hyderabad, 500046, India
| | - Insaf Ahmed Qureshi
- Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Prof. C.R. Rao Road, Hyderabad, 500046, India.
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Morales-Luna L, Hernández-Ochoa B, Martínez-Rosas V, González-Valdez A, Cárdenas-Rodríguez N, Enríquez-Flores S, Marcial-Quino J, Gómez-Manzo S. Cloning, purification, and characterization of the 6-phosphogluconate dehydrogenase (6 PGDH) from Giardia lamblia. Mol Biochem Parasitol 2021; 244:111383. [PMID: 34048823 DOI: 10.1016/j.molbiopara.2021.111383] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 03/21/2021] [Accepted: 05/24/2021] [Indexed: 12/11/2022]
Abstract
Giardia lamblia, due to the habitat in which it develops, requires a continuous supply of intermediate compounds that allow it to survive in the host. The pentose phosphate pathway (PPP) provides essential molecules such as NADPH and ribulose-5-phosphate during the oxidative phase of the pathway. One of the key enzymes during this stage is 6-phosphogluconate dehydrogenase (6 PGDH) for generating NADPH. Given the relevance of the enzyme, in the present work, the 6pgdh gene from G. lamblia was amplified and cloned to produce the recombinant protein (Gl-6 PGDH) and characterize it functionally and structurally after the purification of Gl-6 PGDH by affinity chromatography. The results of the characterization showed that the protein has a molecular mass of 54 kDa, with an optimal pH of 7.0 and a temperature of 36-42 °C. The kinetic parameters of Gl-6 PGDH were Km = 49.2 and 139.9 μM (for NADP+ and 6-PG, respectively), Vmax =26.27 μmol*min-1*mg-1, and Kcat = 24.0 s-1. Finally, computational modeling studies were performed to obtain a structural visualization of the Gl-6 PGDH protein. The generation of the model and the characterization assays will allow us to expand our knowledge for future studies of the function of the protein in the metabolism of the parasite.
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Affiliation(s)
- Laura Morales-Luna
- Laboratorio de Bioquímica Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, 04530, Mexico; Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, 04510, Ciudad de México, Mexico
| | - Beatriz Hernández-Ochoa
- Laboratorio de Inmunoquímica, Hospital Infantil de México Federico Gómez, Secretaría de Salud, 06720, Ciudad de México, Mexico; Programa de Posgrado en Biomedicina y Biotecnología Molecular, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, 11340, Ciudad de México, Mexico
| | - Víctor Martínez-Rosas
- Laboratorio de Bioquímica Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, 04530, Mexico; Programa de Posgrado en Biomedicina y Biotecnología Molecular, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, 11340, Ciudad de México, Mexico
| | - Abigail González-Valdez
- Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, 04510, Ciudad de México, Mexico
| | - Noemi Cárdenas-Rodríguez
- Laboratorio de Neurociencias, Instituto Nacional de Pediatría, Secretaría de Salud, 04530, Ciudad de México, Mexico
| | - Sergio Enríquez-Flores
- Grupo de Investigación en Biomoléculas y Salud Infantil, Laboratorio de EIMyT, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, 04530, Mexico
| | - Jaime Marcial-Quino
- Investigador Independiente en Área de Salud, Ciudad de México, 03303, Mexico
| | - Saúl Gómez-Manzo
- Laboratorio de Bioquímica Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, 04530, Mexico.
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Maturana P, Tobar-Calfucoy E, Fuentealba M, Roversi P, Garratt R, Cabrera R. Crystal structure of the 6-phosphogluconate dehydrogenase from Gluconobacter oxydans reveals tetrameric 6PGDHs as the crucial intermediate in the evolution of structure and cofactor preference in the 6PGDH family. Wellcome Open Res 2021. [DOI: 10.12688/wellcomeopenres.16572.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background: The enzyme 6-phosphogluconate dehydrogenase (6PGDH) is the central enzyme of the oxidative pentose phosphate pathway. Members of the 6PGDH family belong to different classes: either homodimeric enzymes assembled from long-chain subunits or homotetrameric ones assembled from short-chain subunits. Dimeric 6PGDHs bear an internal duplication absent in tetrameric 6PGDHs and distant homologues of the β-hydroxyacid dehydrogenase (βHADH) superfamily. Methods: We use X-ray crystallography to determine the structure of the apo form of the 6PGDH from Gluconobacter oxydans (Go6PGDH). We carried out a structural and phylogenetic analysis of short and long-chain 6PGDHs. We put forward an evolutionary hypothesis explaining the differences seen in oligomeric state vs. dinucleotide preference of the 6PGDH family. We determined the cofactor preference of Go6PGDH at different 6-phosphogluconate concentrations, characterizing the wild-type enzyme and three-point mutants of residues in the cofactor binding site of Go6PGDH. Results: The structural comparison suggests that the 6PG binding site initially evolved by exchanging C-terminal α-helices between subunits. An internal duplication event changed the quaternary structure of the enzyme from a tetrameric to a dimeric arrangement. The phylogenetic analysis suggests that 6PGDHs have spread from Bacteria to Archaea and Eukarya on multiple occasions by lateral gene transfer. Sequence motifs consistent with NAD+- and NADP+-specificity are found in the β2-α2 loop of dimeric and tetrameric 6PGDHs. Site-directed mutagenesis of Go6PGDH inspired by this analysis fully reverses dinucleotide preference. One of the mutants we engineered has the highest efficiency and specificity for NAD+ so far described for a 6PGDH. Conclusions: The family 6PGDH comprises dimeric and tetrameric members whose active sites are conformed by a C-terminal α-helix contributed from adjacent subunits. Dimeric 6PGDHs have evolved from the duplication-fusion of the tetrameric C-terminal domain before independent transitions of cofactor specificity. Changes in the conserved β2-α2 loop are crucial to modulate the cofactor specificity in Go6PGDH.
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Corpas FJ, González-Gordo S, Palma JM. Nitric oxide and hydrogen sulfide modulate the NADPH-generating enzymatic system in higher plants. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:830-847. [PMID: 32945878 DOI: 10.1093/jxb/eraa440] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 09/16/2020] [Indexed: 06/11/2023]
Abstract
Nitric oxide (NO) and hydrogen sulfide (H2S) are two key molecules in plant cells that participate, directly or indirectly, as regulators of protein functions through derived post-translational modifications, mainly tyrosine nitration, S-nitrosation, and persulfidation. These post-translational modifications allow the participation of both NO and H2S signal molecules in a wide range of cellular processes either physiological or under stressful circumstances. NADPH participates in cellular redox status and it is a key cofactor necessary for cell growth and development. It is involved in significant biochemical routes such as fatty acid, carotenoid and proline biosynthesis, and the shikimate pathway, as well as in cellular detoxification processes including the ascorbate-glutathione cycle, the NADPH-dependent thioredoxin reductase (NTR), or the superoxide-generating NADPH oxidase. Plant cells have diverse mechanisms to generate NADPH by a group of NADP-dependent oxidoreductases including ferredoxin-NADP reductase (FNR), NADP-glyceraldehyde-3-phosphate dehydrogenase (NADP-GAPDH), NADP-dependent malic enzyme (NADP-ME), NADP-dependent isocitrate dehydrogenase (NADP-ICDH), and both enzymes of the oxidative pentose phosphate pathway, designated as glucose-6-phosphate dehydrogenase (G6PDH) and 6-phosphogluconate dehydrogenase (6PGDH). These enzymes consist of different isozymes located in diverse subcellular compartments (chloroplasts, cytosol, mitochondria, and peroxisomes) which contribute to the NAPDH cellular pool. We provide a comprehensive overview of how post-translational modifications promoted by NO (tyrosine nitration and S-nitrosation), H2S (persulfidation), and glutathione (glutathionylation), affect the cellular redox status through regulation of the NADP-dependent dehydrogenases.
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Affiliation(s)
- Francisco J Corpas
- Group of Antioxidant, Free Radical and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, CSIC, C/ Profesor Albareda, Granada, Spain
| | - Salvador González-Gordo
- Group of Antioxidant, Free Radical and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, CSIC, C/ Profesor Albareda, Granada, Spain
| | - José M Palma
- Group of Antioxidant, Free Radical and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, CSIC, C/ Profesor Albareda, Granada, Spain
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Sarmiento-Pavía PD, Rodríguez-Hernández A, Rodríguez-Romero A, Sosa-Torres ME. The structure of a novel membrane-associated 6-phosphogluconate dehydrogenase from Gluconacetobacter diazotrophicus (Gd6PGD) reveals a subfamily of short-chain 6PGDs. FEBS J 2020; 288:1286-1304. [PMID: 32621793 DOI: 10.1111/febs.15472] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 06/11/2020] [Accepted: 06/30/2020] [Indexed: 12/14/2022]
Abstract
The enzyme 6-phosphogluconate dehydrogenase catalyzes the conversion of 6-phosphogluconate to ribulose-5-phosphate. It represents an important reaction in the oxidative pentose phosphate pathway, producing a ribose precursor essential for nucleotide and nucleic acid synthesis. We succeeded, for the first time, to determine the three-dimensional structure of this enzyme from an acetic acid bacterium, Gluconacetobacter diazotrophicus (Gd6PGD). Active Gd6PGD, a homodimer (70 kDa), was present in both the soluble and the membrane fractions of the nitrogen-fixing microorganism. The Gd6PGD belongs to the newly described subfamily of short-chain (333 AA) 6PGDs, compared to the long-chain subfamily (480 AA; e.g., Ovis aries, Homo sapiens). The shorter amino acid sequence in Gd6PGD induces the exposition of hydrophobic residues in the C-terminal domain. This distinct structural feature is key for the protein to associate with the membrane. Furthermore, in terms of function, the short-chain 6PGD seems to prefer NAD+ over NADP+ , delivering NADH to the membrane-bound NADH dehydrogenase of the microorganisms required by the terminal oxidases to reduce dioxygen to water for energy conservation. ENZYME: ECnonbreakingspace1.1.1.343. DATABASE: Structural data are available in PDB database under the accession number 6VPB.
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Chen W, Wang Z, Xu W, Tian R, Zeng J. Dibutyl phthalate contamination accelerates the uptake and metabolism of sugars by microbes in black soil. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 262:114332. [PMID: 32182534 DOI: 10.1016/j.envpol.2020.114332] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 02/21/2020] [Accepted: 03/04/2020] [Indexed: 06/10/2023]
Abstract
Dibutyl phthalate (DBP) is widely used as plasticizer and has been detected in the environment, posing a threat to animal health. However, the effects of DBP on agricultural microbiomes are not known. In this study, DBP levels in black soil were evaluated, and the impact of DBP contamination on the uptake and metabolism of sugars in microbes was assessed by glucose absorption tests, metaproteomics, metabolomics, enzyme activity assays and computational simulation analysis. The results indicated that DBP contamination accelerated glucose consumption and upregulated the expression of porins and periplasmic monosaccharide ATP-binding cassette (ABC) transporter solute-binding proteins (SBPs). DBP and its metabolic intermediates (carboxymuconate and butanol) may form a stable complex with sugar transporters and enhance the rigidity and stability of these proteins. Sugar metabolism resulting in the generation of ATP and reducing agent (NADPH), as well as the expression of some key enzymes (dehydrogenases) were also upregulated by DBP treatment. Moreover, a diverse bacterial community appears to utilize sugar, suggesting that there are widespread effects of DBP contamination on soil microbial ecosystems. The results of this study provide a theoretical basis for investigating the toxicological effects of DBP on microbes in black soil.
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Affiliation(s)
- Wenjing Chen
- Center for Ecological Research, Northeast Forestry University, Heilongjiang Province, Harbin, 150040, China; Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, 161006, China; College of Life Sciences, Agriculture and Forestry, Qiqihar University, Heilongjiang Province, Qiqihar, 161006, China.
| | - Zhigang Wang
- Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, 161006, China; College of Life Sciences, Agriculture and Forestry, Qiqihar University, Heilongjiang Province, Qiqihar, 161006, China.
| | - Weihui Xu
- Heilongjiang Provincial Technology Innovation Center of Agromicrobial Preparation Industrialization, Qiqihar, 161006, China; College of Life Sciences, Agriculture and Forestry, Qiqihar University, Heilongjiang Province, Qiqihar, 161006, China.
| | - Renmao Tian
- Institute for Food Safety and Health, Illinois Institute of Technology, Chicago, IL, 60501, USA.
| | - Jin Zeng
- Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing, 210008, China.
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Plasmodium vivax transcriptional profiling of low input cryopreserved isolates through the intraerythrocytic development cycle. PLoS Negl Trop Dis 2020; 14:e0008104. [PMID: 32119669 PMCID: PMC7067476 DOI: 10.1371/journal.pntd.0008104] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 03/12/2020] [Accepted: 01/30/2020] [Indexed: 11/19/2022] Open
Abstract
Approximately one-third of the global population is at risk of Plasmodium vivax infection, and an estimated 7.51 million cases were reported in 2017. Although, P. vivax research is currently limited by the lack of a robust continuous in vitro culture system for this parasite, recent work optimizing short-term ex vivo culture of P. vivax from cryopreserved isolates has facilitated quantitative assays on synchronous parasites. Pairing this improved culture system with low-input Smart-seq2 RNAseq library preparation, we sought to determine whether transcriptional profiling of P. vivax would provide insight into the differential survival of parasites in different culture media. To this end we probed the transcriptional signature of three different ex vivo P. vivax samples in four different culture media using only 1000 cells for each time point taken during the course of the intraerythrocytic development cycle (IDC). Using this strategy, we achieved similar quality transcriptional data to previously reported P. vivax transcriptomes. We found little effect with varying culture media on parasite transcriptional signatures, identified many novel gametocyte-specific genes from transcriptomes of FACS-isolated gametocytes, and determined invasion ligand expression in schizonts in biological isolates and across the IDC. In total, these data demonstrate the feasibility and utility of P. vivax RNAseq-based transcriptomic studies using minimal biomass input to maximize experimental capacity. Plasmodium vivax is the most prevalent malaria-causing parasite species outside of Sub-Saharan Africa and has many unique and poorly understood biological characteristics that make it particularly challenging to study and combat. Transcriptomic profiling of P. vivax under various conditions has the potential to unlock new experimental abilities and aid in elucidating biology and the development of clinical interventions. However, a lack of a robust in vitro culture system for this parasite has restricted transcriptomic studies to researchers with timely access to fresh human isolates from clinics, which often are in resource-poor settings, as well as nearby, well-equipped laboratories for sample processing. This study aimed to gain insight into the differential survival of P. vivax in various culture media from the parasites transcriptional signature in each media. By implementing low-input RNA library preparation strategies, this study obtains robust transcriptomic data at various parasite development stages and in different culture conditions from just 1000 FACS-purified, P. vivax-infected erythrocytes from viable cryopreserved patient isolates. With these data, we find culture media has little effect on transcriptional profile, we characterize invasion ligand expression across intraerythrocytic development and between clinical isolates, and we define the transcriptome of sexual, transmissible stages of the P. vivax parasite. These results highlight the establishment and utility of a powerful platform for studying the transcriptomic biology of this particularly challenging parasite.
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Haeussler K, Berneburg I, Jortzik E, Hahn J, Rahbari M, Schulz N, Preuss J, Zapol'skii VA, Bode L, Pinkerton AB, Kaufmann DE, Rahlfs S, Becker K. Glucose 6-phosphate dehydrogenase 6-phosphogluconolactonase: characterization of the Plasmodium vivax enzyme and inhibitor studies. Malar J 2019; 18:22. [PMID: 30683097 PMCID: PMC6346587 DOI: 10.1186/s12936-019-2651-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 01/16/2019] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Since malaria parasites highly depend on ribose 5-phosphate for DNA and RNA synthesis and on NADPH as a source of reducing equivalents, the pentose phosphate pathway (PPP) is considered an excellent anti-malarial drug target. In Plasmodium, a bifunctional enzyme named glucose 6-phosphate dehydrogenase 6-phosphogluconolactonase (GluPho) catalyzes the first two steps of the PPP. PfGluPho has been shown to be essential for the growth of blood stage Plasmodium falciparum parasites. METHODS Plasmodium vivax glucose 6-phosphate dehydrogenase (PvG6PD) was cloned, recombinantly produced in Escherichia coli, purified, and characterized via enzyme kinetics and inhibitor studies. The effects of post-translational cysteine modifications were assessed via western blotting and enzyme activity assays. Genetically encoded probes were employed to study the effects of G6PD inhibitors on the cytosolic redox potential of Plasmodium. RESULTS Here the recombinant production and characterization of PvG6PD, the C-terminal and NADPH-producing part of PvGluPho, is described. A comparison with PfG6PD (the NADPH-producing part of PfGluPho) indicates that the P. vivax enzyme has higher KM values for the substrate and cofactor. Like the P. falciparum enzyme, PvG6PD is hardly affected by S-glutathionylation and moderately by S-nitrosation. Since there are several naturally occurring variants of PfGluPho, the impact of these mutations on the kinetic properties of the enzyme was analysed. Notably, in contrast to many human G6PD variants, the mutations resulted in only minor changes in enzyme activity. Moreover, nanomolar IC50 values of several compounds were determined on P. vivax G6PD (including ellagic acid, flavellagic acid, and coruleoellagic acid), inhibitors that had been previously characterized on PfGluPho. ML304, a recently developed PfGluPho inhibitor, was verified to also be active on PvG6PD. Using genetically encoded probes, ML304 was confirmed to disturb the cytosolic glutathione-dependent redox potential of P. falciparum blood stage parasites. Finally, a new series of novel small molecules with the potential to inhibit the falciparum and vivax enzymes were synthesized, resulting in two compounds with nanomolar activity. CONCLUSION The characterization of PvG6PD makes this enzyme accessible to further drug discovery activities. In contrast to naturally occurring G6PD variants in the human host that can alter the kinetic properties of the enzyme and thus the redox homeostasis of the cells, the naturally occurring PfGluPho variants studied here are unlikely to have a major impact on the parasites' redox homeostasis. Several classes of inhibitors have been successfully tested and are presently being followed up.
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Affiliation(s)
- Kristina Haeussler
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany
| | - Isabell Berneburg
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany
| | - Esther Jortzik
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany
| | - Julia Hahn
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany
| | - Mahsa Rahbari
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany
| | - Norma Schulz
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany
| | - Janina Preuss
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany.,Conrad Prebys Center for Chemical Genomics, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92037, USA.,Department of Pediatrics, University of California San Diego, San Diego, CA, 92093, USA
| | - Viktor A Zapol'skii
- Institute of Organic Chemistry, Clausthal University of Technology, 38678, Clausthal-Zellerfeld, Germany
| | - Lars Bode
- Department of Pediatrics, University of California San Diego, San Diego, CA, 92093, USA
| | - Anthony B Pinkerton
- Conrad Prebys Center for Chemical Genomics, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92037, USA
| | - Dieter E Kaufmann
- Institute of Organic Chemistry, Clausthal University of Technology, 38678, Clausthal-Zellerfeld, Germany
| | - Stefan Rahlfs
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany
| | - Katja Becker
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany.
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