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Xie Q, Xing H, Wen X, Liu B, Wei Y, Yu Y, Xie X, Song D, Shao G, Xiong Q, Feng Z. Identification of the multiple roles of enolase as an plasminogen receptor and adhesin in Mycoplasma hyopneumoniae. Microb Pathog 2023; 174:105934. [PMID: 36481292 DOI: 10.1016/j.micpath.2022.105934] [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: 08/01/2022] [Revised: 11/07/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022]
Abstract
Mycoplasma hyopneumoniae is the etiological agent underlying porcine enzootic pneumonia, a chronic respiratory disease worldwide. The recruitment of plasminogen to the surface and subsequently promotion of plasmin conversion by the surface-located receptor, have been reported to assist the adhesion and invasion of Mycoplasmas. The surface localization and plasminogen-binding ability of M. hyopneumoniae enolase were previously confirmed; however, the biological functions were not be determined, especially the role as a plasminogen receptor. Here, using ELISA and SPR analyses, we confirmed the stable binding of M. hyopneumoniae enolase to plasminogen in a dose-dependent manner. The facilitation of the activation of plasminogen in the presence of tPA and direct activation of plasminogen at low efficiency without tPA addition by M. hyopneumoniae enolase were also determined using a plasmin-specific chromogenic substrate. Notably, the C-terminal and N-terminal regions located in M. hyopneumoniae enolase play an important role in plasminogen binding and activation. Additionally, we demonstrate that M. hyopneumoniae enolase can competitively inhibit the adherence of M. hyopneumoniae to PK15 cells. These results provide insight into the role of enolase in M. hyopneumoniae infection, a mechanism that manipulates the proteolytic system of the host.
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Affiliation(s)
- Qingyun Xie
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Nanjing, 210014, China
| | - Huixuan Xing
- Institute of Animal Science, Tibet Agricultural and Animal Husbandry College, Linzhi, 860000, China
| | - Xiaoyun Wen
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Beibei Liu
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Nanjing, 210014, China
| | - Yanna Wei
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Nanjing, 210014, China
| | - Yanfei Yu
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Nanjing, 210014, China
| | - Xing Xie
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Nanjing, 210014, China
| | - Daesub Song
- College of Veterinary Medicine, Seoul National University, Seoul, South Korea
| | - Guoqing Shao
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Nanjing, 210014, China
| | - Qiyan Xiong
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Nanjing, 210014, China.
| | - Zhixin Feng
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Nanjing, 210014, China.
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Barroeta-Echegaray E, Fonseca-Liñán R, Argüello-García R, Rodríguez-Muñoz R, Bermúdez-Cruz RM, Nava P, Ortega-Pierres MG. Giardia duodenalis enolase is secreted as monomer during trophozoite-epithelial cell interactions, activates plasminogen and induces necroptotic damage. Front Cell Infect Microbiol 2022; 12:928687. [PMID: 36093180 PMCID: PMC9452966 DOI: 10.3389/fcimb.2022.928687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 08/09/2022] [Indexed: 12/01/2022] Open
Abstract
Enolase, a multifunctional protein expressed by multiple pathogens activates plasminogen to promote proteolysis on components of the extracellular matrix, an important event in early host-pathogen interactions. A secreted form of enolase that is released upon the interaction of trophozoites with epithelial cells has been detected in the secretome of G. duodenalis. However, the role of enolase in the host-pathogen interactions remains largely unknown. In this work, the effects of G. duodenalis enolase (Gd-eno) on the epithelial cell model (IEC-6) were analyzed. Firstly, the coding sequence of Giardia enolase was cloned and the recombinant protein used to raise antibodies that were then used to define the localization and role of enolase in epithelial cell-trophozoite interactions. Gd-eno was detected in small cytoplasmic vesicles as well as at the surface and is enriched in the region of the ventral disk of Giardia trophozoites. Moreover, the blocking of the soluble monomeric form of the enzyme, which is secreted upon interaction with IEC-6 cells by the anti-rGd-eno antibodies, significantly inhibited trophozoite attachment to intestinal IEC-6 cell monolayers. Further, rGd-eno was able to bind human plasminogen (HsPlg) and enhanced plasmin activity in vitro when the trophozoites were incubated with the intrinsic plasminogen activators of epithelial cells. In IEC-6 cells, rGd-eno treatment induced a profuse cell damage characterized by copious vacuolization, intercellular separation and detachment from the substrate; this effect was inhibited by either anti-Gd-eno Abs or the plasmin inhibitor ϵ- aminocaproic acid. Lastly, we established that in epithelial cells rGd-eno treatment induced a necroptotic-like process mediated by tumor necrosis factor α (TNF-α) and the apoptosis inducing factor (AIF), but independent of caspase-3. All together, these results suggest that Giardia enolase is a secreted moonlighting protein that stimulates a necroptotic-like process in IEC-6 epithelial cells via plasminogen activation along to TNFα and AIF activities and must be considered as a virulence factor.
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Affiliation(s)
- Elisa Barroeta-Echegaray
- Department of Genetics and Molecular Biology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Rocío Fonseca-Liñán
- Department of Genetics and Molecular Biology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Raúl Argüello-García
- Department of Genetics and Molecular Biology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Rafael Rodríguez-Muñoz
- Department of Physiology, Biophysics and Neurosciences, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Rosa María Bermúdez-Cruz
- Department of Genetics and Molecular Biology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Porfirio Nava
- Department of Physiology, Biophysics and Neurosciences, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - M. Guadalupe Ortega-Pierres
- Department of Genetics and Molecular Biology, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
- *Correspondence: M. Guadalupe Ortega-Pierres,
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Abstract
Baicalein (BE) is a promising antifungal small-molecule compound with an extended antifungal spectrum, good synergy with fluconazole, and low toxicity, but its target protein and antifungal mechanism remain elusive. In this study, we found that BE can function against Candida albicans by disrupting glycolysis through targeting Eno1 and inhibiting its function. Eno1 acts as a key therapeutic target of the drug, as BE had no antifungal activity against the eno1 null mutant in a Galleria mellonella model of C. albicans infection. To investigate the mechanism of action, we solved the crystal structure of C. albicans Eno1(CaEno1) and then compared the difference between this structure and that of Eno1 from humans. The predicted primary binding site of BE on CaEno1 is between amino acids D261 and W274, with D263, S269, and K273 playing critical roles in the interaction with BE. Both positions S269 and K273 have different residues in the human Eno1 (hEno1). This finding suggests that BE may bind selectively to CaEno1, which would limit the potential for side effects in humans. Our findings demonstrate that Eno1 is a target protein of BE and thus may serve as a novel target for the development of antifungal therapeutics acting through the inhibition of glycolysis. IMPORTANCE Baicalein (BE) is a promising antifungal agent which has been well characterized, but its target protein is still undiscovered. The protein Eno1 plays a crucial role in the survival of Candida albicans. However, there are few antifungal agents which inhibit the functions of Eno1. Here, we found that BE can function against Candida albicans by disrupting glycolysis through targeting Eno1 and inhibiting its function. We further solved the crystal structure of C. albicans Eno1(CaEno1) and predicted that the primary binding site of BE on CaEno1 is between amino acids D261 and W274, with D263, S269, and K273 playing critical roles in the interaction with BE. Our findings will be helpful to get specific small-molecule inhibitors of CaEno1 and open the way for the development of new antifungal therapeutics targeted at inhibiting glycolysis.
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Osorio-Aguilar Y, Gonzalez-Vazquez MC, Hernandez-Ceron DE, Lozano-Zarain P, Martinez-Laguna Y, Gonzalez-Bonilla CR, Rocha-Gracia RDC, Carabarin-Lima A. Structural Characterization of Haemophilus influenzae Enolase and Its Interaction with Human Plasminogen by In Silico and In Vitro Assays. Pathogens 2021; 10:pathogens10121614. [PMID: 34959569 PMCID: PMC8707213 DOI: 10.3390/pathogens10121614] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/03/2021] [Accepted: 12/07/2021] [Indexed: 12/02/2022] Open
Abstract
Haemophilus influenzae is the causal agent of invasive pediatric diseases, such as meningitis, epiglottitis, pneumonia, septic arthritis, pericarditis, cellulitis, and bacteremia (serotype b). Non-typeable H. influenzae (NTHi) strains are associated with localized infections, such as otitis media, conjunctivitis, sinusitis, bronchitis, and pneumonia, and can cause invasive diseases, such as as meningitis and sepsis in immunocompromised hosts. Enolase is a multifunctional protein and can act as a receptor for plasminogen, promoting its activation to plasmin, which leads to the degradation of components of the extracellular matrix, favoring host tissue invasion. In this study, using molecular docking, three important residues involved in plasminogen interaction through the plasminogen-binding motif (251EFYNKENGMYE262) were identified in non-typeable H. influenzae enolase (NTHiENO). Interaction with the human plasminogen kringle domains is conformationally stable due to the formation of four hydrogen bonds corresponding to enoTYR253-plgGLU1 (K2), enoTYR253-plgGLY310 (K3), and enoLYS255-plgARG471/enoGLU251-plgLYS468 (K5). On the other hand, in vitro assays, such as ELISA and far-western blot, showed that NTHiENO is a plasminogen-binding protein. The inhibition of this interaction using polyclonal anti-NTHiENO antibodies was significant. With these results, we can propose that NTHiENO–plasminogen interaction could be one of the mechanisms used by H. influenzae to adhere to and invade host cells.
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Affiliation(s)
- Yesenia Osorio-Aguilar
- Posgrado en Microbiología, Laboratorio de Microbiología Hospitalaria y de la Comunidad, Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla 72570, Mexico; (Y.O.-A.); (M.C.G.-V.); (P.L.-Z.); (Y.M.-L.); (R.d.C.R.-G.)
| | - Maria Cristina Gonzalez-Vazquez
- Posgrado en Microbiología, Laboratorio de Microbiología Hospitalaria y de la Comunidad, Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla 72570, Mexico; (Y.O.-A.); (M.C.G.-V.); (P.L.-Z.); (Y.M.-L.); (R.d.C.R.-G.)
| | | | - Patricia Lozano-Zarain
- Posgrado en Microbiología, Laboratorio de Microbiología Hospitalaria y de la Comunidad, Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla 72570, Mexico; (Y.O.-A.); (M.C.G.-V.); (P.L.-Z.); (Y.M.-L.); (R.d.C.R.-G.)
| | - Ygnacio Martinez-Laguna
- Posgrado en Microbiología, Laboratorio de Microbiología Hospitalaria y de la Comunidad, Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla 72570, Mexico; (Y.O.-A.); (M.C.G.-V.); (P.L.-Z.); (Y.M.-L.); (R.d.C.R.-G.)
| | | | - Rosa del Carmen Rocha-Gracia
- Posgrado en Microbiología, Laboratorio de Microbiología Hospitalaria y de la Comunidad, Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla 72570, Mexico; (Y.O.-A.); (M.C.G.-V.); (P.L.-Z.); (Y.M.-L.); (R.d.C.R.-G.)
| | - Alejandro Carabarin-Lima
- Posgrado en Microbiología, Laboratorio de Microbiología Hospitalaria y de la Comunidad, Centro de Investigaciones en Ciencias Microbiológicas, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla 72570, Mexico; (Y.O.-A.); (M.C.G.-V.); (P.L.-Z.); (Y.M.-L.); (R.d.C.R.-G.)
- Licenciatura en Biotecnología, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Puebla 72570, Mexico
- Correspondence: ; Tel.: +52-(222)-229-5500 (ext. 3965)
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Qiao G, Wu A, Chen X, Tian Y, Lin X. Enolase 1, a Moonlighting Protein, as a Potential Target for Cancer Treatment. Int J Biol Sci 2021; 17:3981-3992. [PMID: 34671213 PMCID: PMC8495383 DOI: 10.7150/ijbs.63556] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 08/11/2021] [Indexed: 12/14/2022] Open
Abstract
Enolase 1 (ENO1) is a moonlighting protein, function as a glycolysis enzyme, a plasminogen receptor and a DNA binding protein. ENO1 play an important role in the process of cancer development. The transcription, translation, post-translational modifying activities and the immunoregulatory role of ENO1 at the cancer development is receiving increasing attention. Some function model studies have shown that ENO1 is a potential target for cancer treatment. In this review, we provide a comprehensive overview of the characterization, function, related transduction cascades of ENO1 and its roles in the pathophysiology of cancers, which is a consequence of ENO1 signaling dysregulation. And the development of novels anticancer agents that targets ENO1 may provide a more attractive option for the treatment of cancers. The data of sarcoma and functional cancer models indicates that ENO1 may become a new potential target for anticancer therapy.
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Affiliation(s)
- Gan Qiao
- School of Pharmacy, Southwest Medical University, Luzhou, 646000, China (Q.G, ).,School of Pharmacy, Central Nervous System Drug Key Laboratory of Sichuan Province, Southwest Medical University, Luzhou, 646000, China
| | - Anguo Wu
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Drugability Evaluation for Chinese Materia Medica, School of Pharmacy, Southwest Medical University, Luzhou, 646000, China.,Education Ministry Key Laboratory of Medical Electrophysiology, Southwest Medical University, Luzhou, 646000, China
| | - Xiaoliang Chen
- Schools of Medicine; Shanxi Datong University, Datong, Shanxi, 037009, China
| | - Ye Tian
- The Eighth Affiliated Hospital Sun Yat-sen University,Shenzhen, Guangdong, China
| | - Xiukun Lin
- College of Life Sci., Shandong University of Technology, Zibo, Shandong, China
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Abstract
Purpose of review Here, we review recent progress made on the genetic characterization of Giardia duodenalis assemblages and their relationship with virulence. We also discuss the implications of virulence factors in the pathogenesis of giardiasis, and advances in the development of vaccines and drugs based on knowledge of virulence markers. Recent findings The use of transcriptomic and proteomic technologies as well as whole genome sequencing (WGS) from single cysts has allowed the assembly of the draft genome sequences for assemblages C and D of G. duodenalis. These findings, along with the published genomes for assemblages A, B, and E, have allowed comparative genomic investigations. In addition, the use of these methodologies for the characterization of the secretomes of trophozoite-epithelial cell interactions for assemblages A/B has led to the identification of virulence markers including energy metabolism enzymes, proteinases, high-cysteine membrane proteins (HCMPs), and variant surface proteins (VSPs). Recently, some drugs and vaccines, targeting virulence factors have been developed, offering possible alternatives to current treatment and prevention options against giardiasis. Summary Among the nine recognized species of Giardia, G. duodenalis stands out because of its broad spectrum of hosts and its socio-economic importance. This species comprises eight genetic assemblages (A to H), of which A and B are zoonotic, and the other assemblages have narrow host specificities. Assemblages A and B may be considered as the most virulent ones, but the existence of asymptomatic carriers and considerable genetic variability within and among these assemblages hampers the definition of common virulence factors. The attachment of Giardia trophozoites to epithelial cells and structural cytoskeleton components of the adhesive disk, such as giardins or tubulins, is proposed to play key roles, but toxins have not yet been precisely defined. However, recent transcriptomic and proteomic analyses of the secretomes of trophozoites representing assemblages A and B and interacting with particular epithelial cell lines have defined a series of virulence factors, including glycolytic (e.g., enolase) and arginolytic (e.g., arginine deiminase) enzymes, cysteine proteases (e.g., giardipain-1) and VSPs (e.g., VSP9B10A). Other factors, such as HCMPs and tenascins, have been consistently found to be excreted/secreted, but their role(s) in the pathogenesis of giardiasis has not yet been elucidated. Interestingly, recent investigations of single cysts representing assemblages C and D using advanced sequencing and informatic methods have suggested that the transcription/expression profiles of virulence factors vary both within and between assemblages, thus assemblage-specific molecules might allow adaptation to the microenvironment within the host. Importantly, some drugs active against cysteine-rich proteins of Giardia, including giardipain-1, VSPs and arginine deiminase, have been shown to be targeted by cysteine-modifying compounds as disulfiram, L-canavanin and allicin. On the other hand, VSPs are presently considered as key vaccine candidates because they induce protection against Giardia in rodents and dogs. Overall, this review reveals that much more work is needed to identify, characterize, and understand the roles of virulence factors in Giardia and to assess their validity as drug and vaccine targets. Clear, advanced omics and informatic tools should assist in this future endeavor, with a focus on targeting virulence factors that are common and/or unique to distinct assemblages to develop new and effective interventions against Giardia.
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Zhou BH, Ding HY, Yang JY, Chai J, Guo HW, Wang HW. Effects of diclazuril on the expression of enolase in second-generation merozoites of Eimeria tenella. Poult Sci 2020; 99:6402-6409. [PMID: 33248555 PMCID: PMC7705050 DOI: 10.1016/j.psj.2020.09.068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 09/20/2020] [Accepted: 09/23/2020] [Indexed: 01/25/2023] Open
Abstract
Eimeria tenella is an obligate intracellular parasite of the chicken cecum; it brings huge economic loss to the chicken industry. Enolase is a multifunctional glycolytic enzyme involved in many processes of parasites, such as infection and migration. In this study, the effect of diclazuril on the expression of enolase in second-generation merozoites of E. tenella (EtENO) was reported. The prokaryotic expression plasmid pET-28a-EtENO was constructed and transformed into Escherichia coli BL21 (DE3). Then, it was subjected to expression under the induction of isopropyl-β-D-1-thiogalactopyranoside. The expressed products were identified and purified. The purified EtENO protein was used for antibody preparation. The EtENO mRNA and protein expression levels were analyzed via real-time PCR and Western blotting. Localization of EtENO on the merozoites was examined by immunofluorescence technique. The mRNA and protein expression levels of EtENO were decreased by 36.3 and 40.36%, respectively, by diclazuril treatment. EtENO distributed in the surface, cytoplasm, and nucleus of the infected/control group. With diclazuril treatment, it was significantly reduced in the surface and cytoplasm and even disappeared in the nucleus of the infected/diclazuril group. These observations suggested that EtENO may play an important role in mechanism of diclazuril anticoccidial action and be a potential drug target for the intervention with E. tenella infection.
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Affiliation(s)
- Bian-Hua Zhou
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471000, Henan, People's Republic of China.
| | - Hai-Yan Ding
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471000, Henan, People's Republic of China
| | - Jing-Yun Yang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471000, Henan, People's Republic of China
| | - Jun Chai
- School of Information Technology and Urban Construction, Luoyang Polytechnic, Luoyang 471934, Henan, People's Republic of China
| | - Hong-Wei Guo
- College of Animal Science & Technology, Henan University of Animal Husbandry and Economy, Zhengzhou 450046, Henan, People's Republic of China
| | - Hong-Wei Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471000, Henan, People's Republic of China
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Ortega-Pierres MG, Argüello-García R. Giardia duodenalis: Role of secreted molecules as virulent factors in the cytotoxic effect on epithelial cells. ADVANCES IN PARASITOLOGY 2019; 106:129-169. [PMID: 31630757 DOI: 10.1016/bs.apar.2019.07.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
During the course of giardiasis in humans and experimental models, G. duodenalis trophozoites express and secrete several proteins (ESPs) affecting structural, cellular and soluble components of the host intestinal milieu. These include the toxin-like molecules CRP136 and ESP58 that induce intestinal hyper-peristalsis. After the completion of the Giardia genome database and using up-to date transcriptomic and proteomic approaches, secreted 'virulence factors' have also been identified and experimentally characterized. This repertoire includes arginine deiminase (ADI) that competes for arginine, an important energy source for trophozoites, some high-cysteine membrane proteins (HCMPs) and VSP88, a versatile variant surface protein (VSP) that functions as an extracellular protease. Another giardial protein, enolase, moonlights as a metabolic enzyme that interacts with the fibrinolytic system and damages host epithelial cells. Other putative Giardia virulence factors are cysteine proteases that degrade multiple host components including mucin, villin, tight junction proteins, immunoglobulins, defensins and cytokines. One of these proteases, named giardipain-1, decreases transepithelial electrical resistance and induces apoptosis in epithelial cells. A putative role for tenascins, present in the Giardia's secretome, is interfering with the host epidermal growth factor. Based on the roles that these molecules play, drugs may be designed to interfere with their functions. This review presents a comprehensive description of secreted Giardia virulence factors. It further describes their cytotoxic mechanisms and roles in the pathophysiology of giardiasis, and then assesses their potential as targets for drug development.
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Affiliation(s)
- M Guadalupe Ortega-Pierres
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de Mexico City, Mexico.
| | - Raúl Argüello-García
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de Mexico City, Mexico
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