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Manning-Cela R, Cortés A, González-Rey E, Van Voorhis WC, Swindle J, González A. LYT1 protein is required for efficient in vitro infection by Trypanosoma cruzi. Infect Immun 2001; 69:3916-23. [PMID: 11349059 PMCID: PMC98423 DOI: 10.1128/iai.69.6.3916-3923.2001] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Trypanosoma cruzi invasion of host cells involves several discrete steps: attachment, parasite internalization mediated by recruitment and fusion of host cell lysosomes, and escape from the parasitophorous vacuole to liberate amastigotes to multiply freely in the cytosol. This report describes the initial characterization of the LYT1 gene and the demonstration that the gene product is involved in cell lysis and infectivity. Mutational analysis demonstrated that deletion of LYT1 resulted in attenuation of infection, which was associated with diminished hemolytic activity. Reintroduction of LYT1 restored infectivity in null mutants, confirming the critical role of LYT1 in infection. Additionally, in vitro stage transition experiments with LYT1-deficient lines showed that these parasites converted to extracellular amastigote-like cells and metacyclic trypomastigotes more rapidly than wild-type parasites, suggesting that the diminished infectivity was not a result of the LYT1 deficiency that affected the parasite's ability to complete the life cycle.
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Bressi JC, Verlinde CLMJ, Aronov AM, Shaw ML, Shin SS, Nguyen LN, Suresh S, Buckner FS, Van Voorhis WC, Kuntz ID, Hol WGJ, Gelb MH. Adenosine analogues as selective inhibitors of glyceraldehyde-3-phosphate dehydrogenase of Trypanosomatidae via structure-based drug design. J Med Chem 2001; 44:2080-93. [PMID: 11405646 PMCID: PMC2957370 DOI: 10.1021/jm000472o] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In our continuation of the structure-based design of anti-trypanosomatid drugs, parasite-selective adenosine analogues were identified as low micromolar inhibitors of glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Crystal structures of Trypanosoma brucei, Trypanosoma cruzi, Leishmania mexicana, and human GAPDH's provided details of how the adenosyl moiety of NAD(+) interacts with the proteins, and this facilitated the understanding of the relative affinities of a series of adenosine analogues for the various GAPDH's. From exploration of modifications of the naphthalenemethyl and benzamide substituents of a lead compound, N(6)-(1-naphthalenemethyl)-2'-deoxy-2'-(3-methoxybenzamido)adenosine (6e), N(6)-(substituted-naphthalenemethyl)-2'-deoxy-2'-(substituted-benzamido)adenosine analogues were investigated. N(6)-(1-Naphthalenemethyl)-2'-deoxy-2'-(3,5-dimethoxybenzamido)adenosine (6m), N(6)-[1-(3-hydroxynaphthalene)methyl]-2'-deoxy-2'-(3,5-dimethoxybenzamido)adenosine (7m), N(6)-[1-(3-methoxynaphthalene)methyl]-2'-deoxy-2'-(3,5-dimethoxybenzamido)adenosine (9m), N(6)-(2-naphthalenemethyl)-2'-deoxy-2'-(3-methoxybenzamido)adenosine (11e), and N(6)-(2-naphthalenemethyl)-2'-deoxy-2'-(3,5-dimethoxybenzamido)adenosine (11m) demonstrated a 2- to 3-fold improvement over 6e and a 7100- to 25000-fold improvement over the adenosine template. IC(50)'s of these compounds were in the range 2-12 microM for T. brucei, T. cruzi, and L. mexicana GAPDH's, and these compounds did not inhibit mammalian GAPDH when tested at their solubility limit. To explore more thoroughly the structure-activity relationships of this class of compounds, a library of 240 N(6)-(substituted)-2'-deoxy-2'-(amido)adenosine analogues was generated using parallel solution-phase synthesis with N(6) and C2' substituents chosen on the basis of computational docking scores. This resulted in the identification of 40 additional compounds that inhibit parasite GAPDH's in the low micromolar range. We also explored adenosine analogues containing 5'-amido substituents and found that 2',5'-dideoxy-2'-(3,5-dimethoxybenzamido)-5'-(diphenylacetamido)adenosine (49) displays an IC(50) of 60-100 microM against the three parasite GAPDH's.
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Affiliation(s)
- Jerome C. Bressi
- Department of Chemistry, University of Washington, Seattle, Washington 98195
| | | | - Alex M. Aronov
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94143
| | - My Le Shaw
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
| | - Sam S. Shin
- Department of Chemistry, University of Washington, Seattle, Washington 98195
| | - Lisa N. Nguyen
- Department of Medicine, University of Washington, Seattle, Washington 98195
| | - Stephen Suresh
- Department of Biological Structure, University of Washington, Seattle, Washington 98195
- Biomolecular Structure Center and Howard Hughes Medical Institute, Seattle, Washington 98195
| | | | | | - Irwin D. Kuntz
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94143
| | - Wim G. J. Hol
- Department of Biological Structure, University of Washington, Seattle, Washington 98195
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
- Biomolecular Structure Center and Howard Hughes Medical Institute, Seattle, Washington 98195
| | - Michael H. Gelb
- Department of Chemistry, University of Washington, Seattle, Washington 98195
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
- To whom correspondence should be addressed. Phone: 206-543-7142. Fax: 206-685-8665.
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