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Vega Hissi EG, De Costa Guardamagna AB, Garro AD, Falcon CR, Anderluh M, Tomašič T, Kikelj D, Yaneff A, Davio CA, Enriz RD, Zurita AR. A Potent N-(piperidin-4-yl)-1H-pyrrole-2-carboxamide Inhibitor of Adenylyl Cyclase of G. lamblia: Biological Evaluation and Molecular Modelling Studies. ChemMedChem 2021; 16:2094-2105. [PMID: 33783977 DOI: 10.1002/cmdc.202100037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 03/26/2021] [Indexed: 11/06/2022]
Abstract
In this work, we report a derivative of N-(piperidin-4-yl)-1H-pyrrole-2-carboxamide as a new inhibitor for adenylyl cyclase of Giardia lamblia which was obtained from a study using structural data of the nucleotidyl cyclase 1 (gNC1) of this parasite. For such a study, we developed a model for this specific enzyme by using homology techniques, which is the first model reported for gNC1 of G. lamblia. Our studies show that the new inhibitor has a competitive mechanism of action against this enzyme. 2-Hydroxyestradiol was used as the reference compound for comparative studies. Results in this work are important from two points of view. on the one hand, an experimentally corroborated model for gNC1 of G. lamblia obtained by molecular modelling is presented; on the other hand, the new inhibitor obtained is an undoubtedly excellent starting structure for the development of new metabolic inhibitors for G. lamblia.
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Affiliation(s)
- Esteban G Vega Hissi
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Instituto Multidisciplinario de Investigaciones Biológicas (IMIBIO-SL), Ejército de los Andes 950, 5700, San Luis, Argentina
| | - Antonella B De Costa Guardamagna
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Instituto Multidisciplinario de Investigaciones Biológicas (IMIBIO-SL), Ejército de los Andes 950, 5700, San Luis, Argentina
| | - Adriana D Garro
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Instituto Multidisciplinario de Investigaciones Biológicas (IMIBIO-SL), Ejército de los Andes 950, 5700, San Luis, Argentina
| | - Cristian R Falcon
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Instituto Multidisciplinario de Investigaciones Biológicas (IMIBIO-SL), Ejército de los Andes 950, 5700, San Luis, Argentina
| | - Marko Anderluh
- Department of Medicinal Chemistry, University of Ljubljana, Faculty of Pharmacy Askerceva, cesta 7, 1000, Ljubljana, Slovenia
| | - Tihomir Tomašič
- Department of Medicinal Chemistry, University of Ljubljana, Faculty of Pharmacy Askerceva, cesta 7, 1000, Ljubljana, Slovenia
| | - Danijel Kikelj
- Department of Medicinal Chemistry, University of Ljubljana, Faculty of Pharmacy Askerceva, cesta 7, 1000, Ljubljana, Slovenia
| | - Agustín Yaneff
- Instituto de Investigaciones Farmacológicas (ININFA-UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, C1113, AAD, Buenos Aires, Argentina
| | - Carlos A Davio
- Instituto de Investigaciones Farmacológicas (ININFA-UBA-CONICET), Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, C1113, AAD, Buenos Aires, Argentina
| | - Ricardo D Enriz
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Instituto Multidisciplinario de Investigaciones Biológicas (IMIBIO-SL), Ejército de los Andes 950, 5700, San Luis, Argentina
| | - Adolfo R Zurita
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Instituto Multidisciplinario de Investigaciones Biológicas (IMIBIO-SL), Ejército de los Andes 950, 5700, San Luis, Argentina
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Drug resistance in Giardia: Mechanisms and alternative treatments for Giardiasis. ADVANCES IN PARASITOLOGY 2020; 107:201-282. [PMID: 32122530 DOI: 10.1016/bs.apar.2019.11.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The use of chemotherapeutic drugs is the main resource against clinical giardiasis due to the lack of approved vaccines. Resistance of G. duodenalis to the most used drugs to treat giardiasis, metronidazole and albendazole, is a clinical issue of growing concern and yet unknown impact, respectively. In the search of new drugs, the completion of the Giardia genome project and the use of biochemical, molecular and bioinformatics tools allowed the identification of ligands/inhibitors for about one tenth of ≈150 potential drug targets in this parasite. Further, the synthesis of second generation nitroimidazoles and benzimidazoles along with high-throughput technologies have allowed not only to define overall mechanisms of resistance to metronidazole but to screen libraries of repurposed drugs and new pharmacophores, thereby increasing the known arsenal of anti-giardial compounds to some hundreds, with most demonstrating activity against metronidazole or albendazole-resistant Giardia. In particular, cysteine-modifying agents which include omeprazole, disulfiram, allicin and auranofin outstand due to their pleiotropic activity based on the extensive repertoire of thiol-containing proteins and the microaerophilic metabolism of this parasite. Other promising agents derived from higher organisms including phytochemicals, lactoferrin and propolis as well as probiotic bacteria/fungi have also demonstrated significant potential for therapeutic and prophylactic purposes in giardiasis. In this context the present chapter offers a comprehensive review of the current knowledge, including commonly prescribed drugs, causes of therapeutic failures, drug resistance mechanisms, strategies for the discovery of new agents and alternative drug therapies.
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Samanta SK, Varghese SS, Krishnan D, Baidya M, Nayak D, Mukherjee S, Ghosh SK. A novel encystation specific protein kinase regulates chitin synthesis in Entamoeba invadens. Mol Biochem Parasitol 2018; 220:19-27. [DOI: 10.1016/j.molbiopara.2018.01.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 11/30/2017] [Accepted: 01/09/2018] [Indexed: 10/18/2022]
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Haubrich BA, Swinney DC. Enzyme Activity Assays for Protein Kinases: Strategies to Identify Active Substrates. Curr Drug Discov Technol 2016; 13:2-15. [PMID: 26768716 DOI: 10.2174/1570163813666160115125930] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 01/13/2016] [Accepted: 01/13/2016] [Indexed: 11/22/2022]
Abstract
Protein kinases are an important class of enzymes and drug targets. New opportunities to discover medicines for neglected diseases can be leveraged by the extensive kinase tools and knowledge created in targeting human kinases. A valuable tool for kinase drug discovery is an enzyme assay that measures catalytic function. The functional assay can be used to identify inhibitors, estimate affinity, characterize molecular mechanisms of action (MMOAs) and evaluate selectivity. However, establishing an enzyme assay for a new kinases requires identification of a suitable substrate. Identification of a new kinase's endogenous physiologic substrate and function can be extremely costly and time consuming. Fortunately, most kinases are promiscuous and will catalyze the phosphotransfer from ATP to alternative substrates with differing degrees of catalytic efficiency. In this manuscript we review strategies and successes in the identification of alternative substrates for kinases from organisms responsible for many of the neglected tropical diseases (NTDs) towards the goal of informing strategies to identify substrates for new kinases. Approaches for establishing a functional kinase assay include measuring auto-activation and use of generic substrates and peptides. The most commonly used generic substrates are casein, myelin basic protein, and histone. Sequence homology modeling can provide insights into the potential substrates and the requirement for activation. Empirical approaches that can identify substrates include screening of lysates (which may also help identify native substrates) and use of peptide arrays. All of these approaches have been used with a varying degree of success to identify alternative substrates.
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Affiliation(s)
- Brad A Haubrich
- Institute for Rare and Neglected Diseases Drug Discovery, 897 Independence Ave, Suite 2C, Mountain View, CA 94043, USA.
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Einarsson E, Svärd SG. Encystation of Giardia intestinalis—a Journey from the Duodenum to the Colon. CURRENT TROPICAL MEDICINE REPORTS 2015. [DOI: 10.1007/s40475-015-0048-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Moon EK, Chung DI, Hong Y, Kong HH. Protein kinase C signaling molecules regulate encystation of Acanthamoeba. Exp Parasitol 2012; 132:524-9. [DOI: 10.1016/j.exppara.2012.07.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Revised: 07/16/2012] [Accepted: 07/23/2012] [Indexed: 01/09/2023]
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Sogame Y, Kojima K, Takeshita T, Fujiwara S, Miyata S, Kinoshita E, Matsuoka T. Protein phosphorylation in encystment-induced Colpoda cucullus: localization and identification of phosphoproteins. FEMS Microbiol Lett 2012; 331:128-35. [DOI: 10.1111/j.1574-6968.2012.02560.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2012] [Revised: 03/23/2012] [Accepted: 03/23/2012] [Indexed: 11/28/2022] Open
Affiliation(s)
- Yoichiro Sogame
- Institute of Biological Science; Faculty of Science; Kochi University; Kochi; Japan
| | - Katsuhiko Kojima
- Department of Microbiology and Immunology; Shinshu University School of Medicine; Nagano; Japan
| | - Toshikazu Takeshita
- Department of Microbiology and Immunology; Shinshu University School of Medicine; Nagano; Japan
| | - Shigeki Fujiwara
- Department of Applied Science; Faculty of Science; Kochi University; Kochi; Japan
| | - Seiji Miyata
- Department of Applied Biology; Kyoto Institute of Technology; Kyoto; Japan
| | - Eiji Kinoshita
- Department of Functional Molecular Science; Graduate School of Biomedical Sciences; Hiroshima University; Hiroshima; Japan
| | - Tatsuomi Matsuoka
- Institute of Biological Science; Faculty of Science; Kochi University; Kochi; Japan
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Abstract
SUMMARYThe ability of cyst-forming protists such asAcanthamoebato escape death by transforming into a cyst form, that is resistant to harsh physiological, environmental and pharmacological conditions, has continued to pose a serious challenge to human and animal health. A complete understanding of the fundamental principles of genome evolution and biochemical pathways of cellular differentiation offers unprecedented opportunities to counter detrimental outcomes.Acanthamoebacan elude inhospitable conditions by forming cysts. Here we unravel the processes involved in the phenotypic switching ofAcanthamoeba, which are critical in our efforts to find potential targets for chemotherapy.
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Manning G, Reiner DS, Lauwaet T, Dacre M, Smith A, Zhai Y, Svard S, Gillin FD. The minimal kinome of Giardia lamblia illuminates early kinase evolution and unique parasite biology. Genome Biol 2011; 12:R66. [PMID: 21787419 PMCID: PMC3218828 DOI: 10.1186/gb-2011-12-7-r66] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2010] [Revised: 05/04/2011] [Accepted: 07/25/2011] [Indexed: 01/23/2023] Open
Abstract
Background The major human intestinal pathogen Giardia lamblia is a very early branching eukaryote with a minimal genome of broad evolutionary and biological interest. Results To explore early kinase evolution and regulation of Giardia biology, we cataloged the kinomes of three sequenced strains. Comparison with published kinomes and those of the excavates Trichomonas vaginalis and Leishmania major shows that Giardia's 80 core kinases constitute the smallest known core kinome of any eukaryote that can be grown in pure culture, reflecting both its early origin and secondary gene loss. Kinase losses in DNA repair, mitochondrial function, transcription, splicing, and stress response reflect this reduced genome, while the presence of other kinases helps define the kinome of the last common eukaryotic ancestor. Immunofluorescence analysis shows abundant phospho-staining in trophozoites, with phosphotyrosine abundant in the nuclei and phosphothreonine and phosphoserine in distinct cytoskeletal organelles. The Nek kinase family has been massively expanded, accounting for 198 of the 278 protein kinases in Giardia. Most Neks are catalytically inactive, have very divergent sequences and undergo extensive duplication and loss between strains. Many Neks are highly induced during development. We localized four catalytically active Neks to distinct parts of the cytoskeleton and one inactive Nek to the cytoplasm. Conclusions The reduced kinome of Giardia sheds new light on early kinase evolution, and its highly divergent sequences add to the definition of individual kinase families as well as offering specific drug targets. Giardia's massive Nek expansion may reflect its distinctive lifestyle, biphasic life cycle and complex cytoskeleton.
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Affiliation(s)
- Gerard Manning
- Razavi Newman Center for Bioinformatics, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
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Cyst and encystment in protozoan parasites: optimal targets for new life-cycle interrupting strategies? Trends Parasitol 2011; 27:450-8. [PMID: 21775209 DOI: 10.1016/j.pt.2011.06.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Revised: 06/15/2011] [Accepted: 06/16/2011] [Indexed: 11/24/2022]
Abstract
Certain protozoan parasites use survival strategies to reside outside the host such as the formation of cysts. This dormant and resistant stage results from the complex process of encystment that involves diverse molecular and cellular modifications. The stimuli and changes associated with cyst biogenesis are a matter of ongoing studies in human and animal protozoan parasites such as amoeba and Giardia species because blocking every step in the encystment pathway should, in theory, interrupt their life cycles. The present review thoroughly examines this essential process in those protozoan parasites and discusses the possibility of using that information to develop new kinds of anti-parasite specific and life cycle-interrupting drugs, aimed at holding back the dissemination of these infections.
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Moon EK, Chung DI, Hong Y, Kong HH. Expression levels of encystation mediating factors in fresh strain of Acanthamoeba castellanii cyst ESTs. Exp Parasitol 2011; 127:811-6. [DOI: 10.1016/j.exppara.2011.01.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 12/22/2010] [Accepted: 01/11/2011] [Indexed: 11/25/2022]
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Bittencourt-Silvestre J, Lemgruber L, de Souza W. Encystation process of Giardia lamblia: morphological and regulatory aspects. Arch Microbiol 2010; 192:259-65. [PMID: 20151113 DOI: 10.1007/s00203-010-0554-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2009] [Revised: 01/24/2010] [Accepted: 01/27/2010] [Indexed: 12/21/2022]
Abstract
One important step in the life cycle of the pathogenic protozoan Giardia lamblia is the transformation of the proliferative form, the trophozoite, into the non-proliferative cyst. This process, known as encystation, can be triggered in vitro. Morphological analysis showed that during trophozoite-cyst transformation, major changes take place: modification of the protozoan shape, internalization of the flagella, fragmentation of the adhesive disk, and appearance of encystation vesicles (ESVs), which later on fuse with the plasma membrane forming the cell wall. Sites of attachment of these vesicles to the inner portion of the protozoan plasma membrane were observed 6 h after the beginning of the encystation process. These sites were only visible when we used high-resolution scanning electron microscopy to study Giardia surface. In order to analyze the involvement of protein kinases and phosphatases on the encystation process, inhibitors of these enzymes were added to the culture medium, and their effect on the differentiation process was determined using light, immunofluorescence, and electron microscopy. Significant inhibition was observed with LY294002, an inhibitor of PI3 kinase; genistein, an inhibitor of tyrosine kinase; and staurosporine, at concentrations, which inhibit protein kinase C. Okadaic acid, an inhibitor or protein phosphatase, and wortmannin, an inhibitor of PI3K, did not interfere with the encystation process. However, they induced the appearance of large and pleomorphic forms where several nuclei and disorganization of the peripheral vesicles were observed.
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Sonda S, Morf L, Bottova I, Baetschmann H, Rehrauer H, Caflisch A, Hakimi MA, Hehl AB. Epigenetic mechanisms regulate stage differentiation in the minimized protozoan Giardia lamblia. Mol Microbiol 2010; 76:48-67. [PMID: 20132448 DOI: 10.1111/j.1365-2958.2010.07062.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Histone modification is an important mechanism regulating both gene expression and the establishment and maintenance of cellular phenotypes during development. Regulation of histone acetylation via histone acetylases and deacetylases (HDACs) appears to be particularly crucial in determining gene expression patterns. In this study we explored the effect of HDAC inhibition on the life cycle of the human pathogen Giardia lamblia, a highly reduced parasitic protozoan characterized by minimized cellular processes. We found that the HDAC inhibitor FR235222 increased the level of histone acetylation and induced transcriptional regulation of approximately 2% of genes in proliferating and encysting parasites. In addition, our analyses showed that the levels of histone acetylation decreased during differentiation into cysts, the infective stage of the parasite. Importantly, FR235222 treatment during encystation reversed this histone hypo-acetylation and potently blocked the formation of cysts. These results provide the first direct evidence for epigenetic regulation of gene expression in this simple eukaryote. This suggests that regulation of histone acetylation is involved in the control of Giardia stage differentiation, and identifies epigenetic mechanisms as a promising target to prevent Giardia transmission.
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Affiliation(s)
- Sabrina Sonda
- Institute of Parasitology, University of Zürich, Zürich, Switzerland.
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Carranza PG, Lujan HD. New insights regarding the biology of Giardia lamblia. Microbes Infect 2010; 12:71-80. [DOI: 10.1016/j.micinf.2009.09.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Accepted: 09/15/2009] [Indexed: 10/20/2022]
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Protein kinase C signalling during miracidium to mother sporocyst development in the helminth parasite, Schistosoma mansoni. Int J Parasitol 2009; 39:1223-33. [DOI: 10.1016/j.ijpara.2009.04.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Revised: 03/31/2009] [Accepted: 04/02/2009] [Indexed: 12/27/2022]
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Belaunzarán ML, Lammel EM, Giménez G, Wainszelbaum MJ, de Isola ELD. Involvement of protein kinase C isoenzymes in Trypanosoma cruzi metacyclogenesis induced by oleic acid. Parasitol Res 2009; 105:47-55. [PMID: 19205738 DOI: 10.1007/s00436-009-1359-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Accepted: 01/23/2009] [Indexed: 12/01/2022]
Abstract
Previously, we showed that oleic acid (OA) induces Trypanosoma cruzi metacyclogenesis through a signaling pathway involving de novo diacylglycerol biosynthesis and simultaneous protein kinase C (PKC) activation. Herein, we demonstrated that OA also triggers a transient Ca(2+) signal in epimastigotes, necessary for parasite differentiation, that could account for PKC activation. In addition, we found that this free fatty acid (FFA) directly stimulated in vitro the activity of T. cruzi PKC in a dose-response way. We determined the presence of classical and novel PKC isoenzymes that were differentially expressed in the infective amastigotes (alpha and delta) and tripomastigotes (alpha, beta, and gamma) and in the non-infective epimastigotes (alpha, beta, gamma, and delta). We also demonstrated that OA induced in epimastigotes the translocation of PKC alpha, beta, gamma, and delta to the membrane, indicating a selective effect of this FFA. To establish a correlation between T. cruzi metacyclogenesis induced by OA and the activation of a particular PKC isoenzyme, the specific PKC inhibitors Ro 32-0432 and Rottlerin (9-30 nM and 5-35 microM, respectively) were employed. These compounds, even at the lowest concentrations assayed, abrogated both epimastigote differentiation and membrane translocation of PKC beta, gamma, and delta. These findings strongly support a key role for classical and novel PKC isoenzymes in the signaling pathways involved in T. cruzi metacyclogenesis induced by OA.
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Affiliation(s)
- María Laura Belaunzarán
- Departamento de Microbiología, Parasitología e Inmunología, Universidad de Buenos Aires, Argentina.
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Moon EK, Chung DI, Hong YC, Ahn TI, Kong HH. Acanthamoeba castellanii: Gene profile of encystation by ESTs analysis and KOG assignment. Exp Parasitol 2008; 119:111-6. [PMID: 18280471 DOI: 10.1016/j.exppara.2008.01.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2007] [Revised: 11/27/2007] [Accepted: 01/02/2008] [Indexed: 10/22/2022]
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Encystation of Giardia lamblia: a model for other parasites. Curr Opin Microbiol 2007; 10:554-9. [PMID: 17981075 DOI: 10.1016/j.mib.2007.09.011] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2007] [Revised: 09/20/2007] [Accepted: 09/20/2007] [Indexed: 01/24/2023]
Abstract
To colonize the human small intestine, Giardia lamblia monitors a dynamic environment. Trophozoites attach to enterocytes that mature and die. The parasites must 'decide' whether to re-attach or differentiate into cysts that survive in the environment and re-activate when ingested. Other intestinal parasites face similar challenges. Study of these parasites is limited because they do not encyst in vitro. Giardia trophozoites were persuaded to encyst in vitro by mimicking physiological stimuli. Cysts are dormant, yet 'spring-loaded for action' to excyst upon ingestion. Giardial encystation has been studied from morphological, cell biological, biochemical, and molecular viewpoints. Yet important gaps remain and the mechanisms that co-ordinate responses to external signals remain enigmatic.
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