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Abass S, Parveen R, Irfan M, Malik Z, Husain SA, Ahmad S. Mechanism of antibacterial phytoconstituents: an updated review. Arch Microbiol 2024; 206:325. [PMID: 38913205 DOI: 10.1007/s00203-024-04035-y] [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: 04/25/2024] [Accepted: 06/05/2024] [Indexed: 06/25/2024]
Abstract
The increase of multiple drug resistance bacteria significantly diminishes the effectiveness of antibiotic armory and subsequently exaggerates the level of therapeutic failure. Phytoconstituents are exceptional substitutes for resistance-modifying vehicles. The plants appear to be a deep well for the discovery of novel antibacterial compounds. This is owing to the numerous enticing characteristics of plants, they are easily accessible and inexpensive, extracts or chemicals derived from plants typically have significant levels of action against infections, and they rarely cause serious adverse effects. The enormous selection of phytochemicals offers very distinct chemical structures that may provide both novel mechanisms of antimicrobial activity and deliver us with different targets in the interior of the bacterial cell. They can directly affect bacteria or act together with the crucial events of pathogenicity, in this manner decreasing the aptitude of bacteria to create resistance. Abundant phytoconstituents demonstrate various mechanisms of action toward multi drug resistance bacteria. Overall, this comprehensive review will provide insights into the potential of phytoconstituents as alternative treatments for bacterial infections, particularly those caused by multi drug resistance strains. By examining the current state of research in this area, the review will shed light on potential future directions for the development of new antimicrobial therapies.
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Affiliation(s)
- Sageer Abass
- Department of Biotechnology, Jamia Millia Islamia, New Delhi, 110025, India
- Department of Biosciences, Jamia Millia Islamia, New Delhi, 110025, India
- Centre of Excellence in Unani Medicine (Pharmacognosy and Pharmacology), Bioactive Natural Product Laboratory, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, 110062, India
| | - Rabea Parveen
- Centre of Excellence in Unani Medicine (Pharmacognosy and Pharmacology), Bioactive Natural Product Laboratory, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, 110062, India
| | - Mohammad Irfan
- Department of Biotechnology, Jamia Millia Islamia, New Delhi, 110025, India
- Department of Biosciences, Jamia Millia Islamia, New Delhi, 110025, India
| | - Zoya Malik
- Department of Biosciences, Jamia Millia Islamia, New Delhi, 110025, India
- Centre of Excellence in Unani Medicine (Pharmacognosy and Pharmacology), Bioactive Natural Product Laboratory, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, 110062, India
| | - Syed Akhtar Husain
- Department of Biosciences, Jamia Millia Islamia, New Delhi, 110025, India
| | - Sayeed Ahmad
- Centre of Excellence in Unani Medicine (Pharmacognosy and Pharmacology), Bioactive Natural Product Laboratory, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, 110062, India.
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Kim D, Choi H, Oh H, Lee J, Hwang Y, Kang SS. Mutanolysin-Digested Peptidoglycan of Lactobacillus reuteri Promotes the Inhibition of Porphyromonas gingivalis Lipopolysaccharide-Induced Inflammatory Responses through the Regulation of Signaling Cascades via TLR4 Suppression. Int J Mol Sci 2023; 25:42. [PMID: 38203215 PMCID: PMC10779245 DOI: 10.3390/ijms25010042] [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: 11/01/2023] [Revised: 12/08/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024] Open
Abstract
Periodontitis is an oral infectious disease caused by various pathogenic bacteria, such as Porphyromonas gingivalis. Although probiotics and their cellular components have demonstrated positive effects on periodontitis, the beneficial impact of peptidoglycan (PGN) from probiotic Lactobacillus remains unclear. Therefore, our study sought to investigate the inhibitory effect of PGN isolated from L. reuteri (LrPGN) on P. gingivalis-induced inflammatory responses. Pretreatment with LrPGN significantly inhibited the production of interleukin (IL)-1β, IL-6, and CCL20 in RAW 264.7 cells induced by P. gingivalis lipopolysaccharide (LPS). LrPGN reduced the phosphorylation of PI3K/Akt and MAPKs, as well as NF-κB activation, which were induced by P. gingivalis LPS. Furthermore, LrPGN dose-dependently reduced the expression of Toll-like receptor 4 (TLR4), indicating that LrPGN inhibits periodontal inflammation by regulating cellular signaling cascades through TLR4 suppression. Notably, LrPGN exhibited stronger inhibition of P. gingivalis LPS-induced production of inflammatory mediators compared to insoluble LrPGN and proteinase K-treated LrPGN. Moreover, MDP, a minimal bioactive PGN motif, also dose-dependently inhibited P. gingivalis LPS-induced inflammatory mediators, suggesting that MDP-like molecules present in the LrPGN structure may play a crucial role in the inhibition of inflammatory responses. Collectively, these findings suggest that LrPGN can mitigate periodontal inflammation and could be a useful agent for the prevention and treatment of periodontitis.
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Affiliation(s)
- Donghan Kim
- Department of Food Science and Biotechnology, College of Life Science and Biotechnology, Dongguk University, Goyang 10326, Republic of Korea
| | - Hanhee Choi
- Department of Food Science and Biotechnology, College of Life Science and Biotechnology, Dongguk University, Goyang 10326, Republic of Korea
| | - Hyeonjun Oh
- Department of Food Science and Biotechnology, College of Life Science and Biotechnology, Dongguk University, Goyang 10326, Republic of Korea
| | - Jiyeon Lee
- Department of Food Science and Biotechnology, College of Life Science and Biotechnology, Dongguk University, Goyang 10326, Republic of Korea
| | - Yongjin Hwang
- Novalacto Co., Ltd., Daejon 34016, Republic of Korea
| | - Seok-Seong Kang
- Department of Food Science and Biotechnology, College of Life Science and Biotechnology, Dongguk University, Goyang 10326, Republic of Korea
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Stasiak AC, Gogler K, Borisova M, Fink P, Mayer C, Stehle T, Zocher G. N-acetylmuramic acid recognition by MurK kinase from the MurNAc auxotrophic oral pathogen Tannerella forsythia. J Biol Chem 2023; 299:105076. [PMID: 37481208 PMCID: PMC10465942 DOI: 10.1016/j.jbc.2023.105076] [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: 05/08/2023] [Revised: 07/14/2023] [Accepted: 07/17/2023] [Indexed: 07/24/2023] Open
Abstract
The bacterial cell wall consists of a three-dimensional peptidoglycan layer, composed of peptides linked to the sugars N-acetylmuramic acid (MurNAc) and GlcNAc. Unlike other bacteria, the pathogenic Tannerella forsythia, a member of the red complex group of bacteria associated with the late stages of periodontitis, lacks biosynthetic pathways for MurNAc production and therefore obtains MurNAc from the environment. Sugar kinases play a crucial role in the MurNAc recycling process, activating the sugar molecules by phosphorylation. In this study, we present the first crystal structures of a MurNAc kinase, called murein sugar kinase (MurK), in its unbound state as well as in complexes with the ATP analog β-γ-methylene adenosine triphosphate (AMP-PCP) and with MurNAc. We also determined the crystal structures of K1058, a paralogous MurNAc kinase of T. forsythia, in its unbound state and in complex with MurNAc. We identified the active site and residues crucial for MurNAc specificity as the less bulky side chains of S133, P134, and L135, which enlarge the binding cavity for the lactyl ether group, unlike the glutamate or histidine residues present in structural homologs. In establishing the apparent kinetic parameters for both enzymes, we showed a comparable affinity for MurNAc (Km 180 μM and 30 μM for MurK and K1058, respectively), with MurK being over two hundred times faster than K1058 (Vmax 80 and 0.34 μmol min-1 mg-1, respectively). These data might support a structure-guided approach to development of inhibitory MurNAc analogs for pathogen MurK enzymes.
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Affiliation(s)
| | - Karolin Gogler
- Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen, Germany
| | - Marina Borisova
- Interfaculty Institute of Microbiology and Infection Medicine, Organismic Interactions/Glycobiology, University of Tuebingen, Tuebingen, Germany
| | - Phillipp Fink
- Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen, Germany
| | - Christoph Mayer
- Interfaculty Institute of Microbiology and Infection Medicine, Organismic Interactions/Glycobiology, University of Tuebingen, Tuebingen, Germany
| | - Thilo Stehle
- Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen, Germany
| | - Georg Zocher
- Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen, Germany.
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NamZ1 and NamZ2 from the oral pathogen Tannerella forsythia are peptidoglycan processing exo-β- N-acetylmuramidases with distinct substrate specificity. J Bacteriol 2022; 204:e0059721. [PMID: 35129368 DOI: 10.1128/jb.00597-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Gram-negative periodontal pathogen Tannerella forsythia is inherently auxotrophic for N-acetylmuramic acid (MurNAc), which is an essential carbohydrate constituent of the peptidoglycan (PGN) of the bacterial cell wall. Thus, to build up its cell wall, T. forsythia strictly depends on the salvage of exogenous MurNAc or sources of MurNAc, such as polymeric or fragmentary PGN, derived from cohabiting bacteria within the oral microbiome. In our effort to elucidate how T. forsythia satisfies its demand for MurNAc, we recognized that the organism possesses three putative orthologs of the exo-β-N-acetylmuramidase BsNamZ from Bacillus subtilis, which cleaves non-reducing end, terminal MurNAc entities from the artificial substrate pNP-MurNAc and the naturally-occurring disaccharide substrate MurNAc-N-acetylglucosamine (GlcNAc). TfNamZ1 and TfNamZ2 were successfully purified as soluble, pure recombinant His6-fusions and characterized as exo-lytic β-N-acetylmuramidases with distinct substrate specificities. The activity of TfNamZ1 was considerably lower compared to TfNamZ2 and BsNamZ, in the cleavage of MurNAc-GlcNAc. When peptide-free PGN glycans were used as substrates, we revealed striking differences in the specificity and mode of action of these enzymes, as analyzed by mass spectrometry. TfNamZ1, but not TfNamZ2 or BsNamZ, released GlcNAc-MurNAc disaccharides from these glycans. In addition, glucosamine (GlcN)-MurNAc disaccharides were generated when partially N-deacetylated PGN glycans from B. subtilis 168 were applied. This characterizes TfNamZ1 as a unique disaccharide-forming exo-lytic β-N-acetylmuramidase (exo-disaccharidase), and, TfNamZ2 and BsNamZ as sole MurNAc monosaccharide-lytic exo-β-N-acetylmuramidases. IMPORTANCE Two exo-N-acetylmuramidases from T. forsythia belonging to glycosidase family GH171 (www.cazy.org) were shown to differ in their activities, thus revealing a functional diversity within this family: NamZ1 releases disaccharides (GlcNAc-MurNAc/GlcN-MurNAc) from the non-reducing ends of PGN glycans, whereas NamZ2 releases terminal MurNAc monosaccharides. This work provides a better understanding of how T. forsythia may acquire the essential growth factor MurNAc by the salvage of PGN from cohabiting bacteria in the oral microbiome, which may pave avenues for the development of anti-periodontal drugs. On a broad scale, our study indicates that the utilization of PGN as a nutrient source, involving exo-lytic N-acetylmuramidases with different modes of action, appears to be a general feature of bacteria, particularly among the phylum Bacteroidetes.
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Hottmann I, Borisova M, Schäffer C, Mayer C. Peptidoglycan Salvage Enables the Periodontal Pathogen Tannerella forsythia to Survive within the Oral Microbial Community. Microb Physiol 2021; 31:123-134. [PMID: 34107471 DOI: 10.1159/000516751] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 04/22/2021] [Indexed: 11/19/2022]
Abstract
Tannerella forsythia is an anaerobic, fusiform Gram-negative oral pathogen strongly associated with periodontitis, a multibacterial inflammatory disease that leads to the destruction of the teeth-supporting tissue, ultimately causing tooth loss. To survive in the oral habitat, T. forsythia depends on cohabiting bacteria for the provision of nutrients. For axenic growth under laboratory conditions, it specifically relies on the external supply of N-acetylmuramic acid (MurNAc), which is an essential constituent of the peptidoglycan (PGN) of bacterial cell walls. T. forsythia comprises a typical Gram-negative PGN; however, as evidenced by genome sequence analysis, the organism lacks common enzymes required for the de novo synthesis of precursors of PGN, which rationalizes its MurNAc auxotrophy. Only recently insights were obtained into how T. forsythia gains access to MurNAc in its oral habitat, enabling synthesis of the own PGN cell wall. This report summarizes T. forsythia's strategies to survive in the oral habitat by means of PGN salvage pathways, including recovery of exogenous MurNAc and PGN-derived fragments but also polymeric PGN, which are all derived from cohabiting bacteria either via cell wall turnover or decay of cells. Salvage of polymeric PGN presumably requires the removal of peptides from PGN by an unknown amidase, concomitantly with the translocation of the polymer across the outer membrane. Two recently identified exo-lytic N-acetylmuramidases (Tf_NamZ1 and Tf_NamZ2) specifically cleave the peptide-free, exogenous (nutrition source) PGN in the periplasm and release the MurNAc and disaccharide substrates for the transporters Tf_MurT and Tf_AmpG, respectively, whereas the peptide-containing, endogenous (the self-cell wall) PGN stays unattached. This review also outlines how T. forsythia synthesises the PGN precursors UDP-MurNAc and UDP-N-acetylglucosamine (UDP-GlcNAc), involving homologs of the Pseudomonas sp. recycling enzymes AmgK/MurU and a monofunctional uridylyl transferase (named Tf_GlmU*), respectively.
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Affiliation(s)
- Isabel Hottmann
- Interfaculty Institute of Microbiology and Infection Medicine, Organismic Interactions/Glycobiology, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Marina Borisova
- Interfaculty Institute of Microbiology and Infection Medicine, Organismic Interactions/Glycobiology, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Christina Schäffer
- Department of NanoBiotechnology, NanoGlycobiology Unit, Universität für Bodenkultur Wien, Vienna, Austria
| | - Christoph Mayer
- Interfaculty Institute of Microbiology and Infection Medicine, Organismic Interactions/Glycobiology, Eberhard Karls Universität Tübingen, Tübingen, Germany
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Mayer VMT, Tomek MB, Figl R, Borisova M, Hottmann I, Blaukopf M, Altmann F, Mayer C, Schäffer C. Utilization of different MurNAc sources by the oral pathogen Tannerella forsythia and role of the inner membrane transporter AmpG. BMC Microbiol 2020; 20:352. [PMID: 33203363 PMCID: PMC7670621 DOI: 10.1186/s12866-020-02006-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 10/12/2020] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND The Gram-negative oral pathogen Tannerella forsythia strictly depends on the external supply of the essential bacterial cell wall sugar N-acetylmuramic acid (MurNAc) for survival because of the lack of the common MurNAc biosynthesis enzymes MurA/MurB. The bacterium thrives in a polymicrobial biofilm consortium and, thus, it is plausible that it procures MurNAc from MurNAc-containing peptidoglycan (PGN) fragments (muropeptides) released from cohabiting bacteria during natural PGN turnover or cell death. There is indirect evidence that in T. forsythia, an AmpG-like permease (Tanf_08365) is involved in cytoplasmic muropeptide uptake. In E. coli, AmpG is specific for the import of N-acetylglucosamine (GlcNAc)-anhydroMurNAc(-peptides) which are common PGN turnover products, with the disaccharide portion as a minimal requirement. Currently, it is unclear which natural, complex MurNAc sources T. forsythia can utilize and which role AmpG plays therein. RESULTS We performed a screen of various putative MurNAc sources for T. forsythia mimicking the situation in the natural habitat and compared bacterial growth and cell morphology of the wild-type and a mutant lacking AmpG (T. forsythia ΔampG). We showed that supernatants of the oral biofilm bacteria Porphyromonas gingivalis and Fusobacterium nucleatum, and of E. coli ΔampG, as well as isolated PGN and defined PGN fragments obtained after enzymatic digestion, namely GlcNAc-anhydroMurNAc(-peptides) and GlcNAc-MurNAc(-peptides), could sustain growth of T. forsythia wild-type, while T. forsythia ΔampG suffered from growth inhibition. In supernatants of T. forsythia ΔampG, the presence of GlcNAc-anhMurNAc and, unexpectedly, also GlcNAc-MurNAc was revealed by tandem mass spectrometry analysis, indicating that both disaccharides are substrates of AmpG. The importance of AmpG in the utilization of PGN fragments as MurNAc source was substantiated by a significant ampG upregulation in T. forsythia cells cultivated with PGN, as determined by quantitative real-time PCR. Further, our results indicate that PGN-degrading amidase, lytic transglycosylase and muramidase activities in a T. forsythia cell extract are involved in PGN scavenging. CONCLUSION T. forsythia metabolizes intact PGN as well as muropeptides released from various bacteria and the bacterium's inner membrane transporter AmpG is essential for growth on these MurNAc sources, and, contrary to the situation in E. coli, imports both, GlcNAc-anhMurNAc and GlcNAc-MurNAc fragments.
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Affiliation(s)
- Valentina M T Mayer
- Department of NanoBiotechnology, NanoGlycobiology unit, Universität für Bodenkultur Wien, Vienna, Austria
| | - Markus B Tomek
- Department of NanoBiotechnology, NanoGlycobiology unit, Universität für Bodenkultur Wien, Vienna, Austria
| | - Rudolf Figl
- Department of Chemistry, Institute of Biochemistry, Universität für Bodenkultur Wien, Vienna, Austria
| | - Marina Borisova
- Department of Biology, Eberhard Karls Universität Tübingen, Microbiology/Glycobiology, Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Tübingen, Germany
| | - Isabel Hottmann
- Department of Biology, Eberhard Karls Universität Tübingen, Microbiology/Glycobiology, Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Tübingen, Germany
| | - Markus Blaukopf
- Department of Chemistry, Institute of Organic Chemistry, Universität für Bodenkultur Wien, Vienna, Austria
| | - Friedrich Altmann
- Department of Chemistry, Institute of Biochemistry, Universität für Bodenkultur Wien, Vienna, Austria
| | - Christoph Mayer
- Department of Biology, Eberhard Karls Universität Tübingen, Microbiology/Glycobiology, Interfaculty Institute of Microbiology and Infection Medicine Tübingen, Tübingen, Germany.
| | - Christina Schäffer
- Department of NanoBiotechnology, NanoGlycobiology unit, Universität für Bodenkultur Wien, Vienna, Austria.
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Trinh NTT, Tran HQ, Van Dong Q, Cambillau C, Roussel A, Leone P. Crystal structure of Type IX secretion system PorE C-terminal domain from Porphyromonas gingivalis in complex with a peptidoglycan fragment. Sci Rep 2020; 10:7384. [PMID: 32355178 PMCID: PMC7192894 DOI: 10.1038/s41598-020-64115-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 03/31/2020] [Indexed: 02/06/2023] Open
Abstract
Porphyromonas gingivalis, the major human pathogen associated to periodontal diseases, utilizes the Bacteroidetes-specific type IX secretion system (T9SS) to export virulence factors. PorE is a periplasmic multi-domain lipoprotein associated to the outer membrane that was recently identified as essential for T9SS function. Little is known on T9SS at the structural level, and in particular its interaction with peptidoglycan. This prompted us to carry out structural studies on PorE full length as well as on its four isolated domains. Here we report the crystal structure of the C-terminal OmpA_C-like putative peptidoglycan-binding domain at 1.55 Å resolution. An electron density volume was identified in the protein cleft, making it possible to build a naturally-occurring peptidoglycan fragment. This result suggests that PorE interacts with peptidoglycan and that PorE could anchor T9SS to the cell wall.
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Affiliation(s)
- Nhung Thi Trang Trinh
- Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, UMR 7257, 163 Avenue de Luminy, Case 932, 13009, Marseille, France.,Architecture et Fonction des Macromolécules Biologiques, Centre National de la Recherche Scientifique, UMR 7257, 163 Avenue de Luminy, Case 932, 13009, Marseille, France.,Faculty of Medical Technology, PHENIKAA University, Yen Nghia, Ha Dong, Hanoi 12116, Vietnam.,PHENIKAA Research and Technology Institute (PRATI), A&A Green Phoenix Group JSC, No. 167 Hoang Ngan, Trung Hoa, Cau Giay, Hanoi 11313, Vietnam
| | - Hieu Quang Tran
- Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, UMR 7257, 163 Avenue de Luminy, Case 932, 13009, Marseille, France.,Architecture et Fonction des Macromolécules Biologiques, Centre National de la Recherche Scientifique, UMR 7257, 163 Avenue de Luminy, Case 932, 13009, Marseille, France
| | - Quyen Van Dong
- Institute of Biotechnology, Vietnam Academy of Science and Technology. 18 Hoang Quoc Viet, Ha Noi, Vietnam.,University of Science and Technology of Hanoi, Vietnam Academy of Science and Technology. 18 Hoang Quoc Viet, Ha Noi, Vietnam
| | - Christian Cambillau
- Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, UMR 7257, 163 Avenue de Luminy, Case 932, 13009, Marseille, France.,Architecture et Fonction des Macromolécules Biologiques, Centre National de la Recherche Scientifique, UMR 7257, 163 Avenue de Luminy, Case 932, 13009, Marseille, France
| | - Alain Roussel
- Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, UMR 7257, 163 Avenue de Luminy, Case 932, 13009, Marseille, France.,Architecture et Fonction des Macromolécules Biologiques, Centre National de la Recherche Scientifique, UMR 7257, 163 Avenue de Luminy, Case 932, 13009, Marseille, France
| | - Philippe Leone
- Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, UMR 7257, 163 Avenue de Luminy, Case 932, 13009, Marseille, France. .,Architecture et Fonction des Macromolécules Biologiques, Centre National de la Recherche Scientifique, UMR 7257, 163 Avenue de Luminy, Case 932, 13009, Marseille, France.
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