Abstract:
:The major proteolytic activity of Trypanosoma cruzi is a cathepsin L-like cysteine protease expressed in all stages of the parasite. As an initial step in identifying possible functions of this enzyme in the life cycle of T. cruzi, and examining its potential as a target for rational drug design, two fluoromethyl ketone-derivatized cysteine protease inhibitors were studied for their effects on T. cruzi infection of mammalian cells. Both inhibitors are irreversible substrate analogues with high specificity for cysteine proteases and minimal toxicity to mammalian cells. While micromolar concentrations of inhibitors had some effect on replication of all parasite stages, the most dramatic arrest of parasite replication occurred at the transformation of trypomastigote to amastigote, and also from amastigote to trypomastigote. It is therefore proposed that the enzyme functions in intracellular protein degradation in some stages of T. cruzi, but also in remodeling of the parasite during transformation between stages. Concentrations of inhibitors necessary to interrupt the parasite life cycle had no observable toxicity to macrophages, fibroblasts or epithelial cells in culture. Differential susceptibility of T. cruzi versus host cysteine proteases to fluoromethyl ketone protease inhibitors suggests that inhibition of the T. cruzi cysteine protease is a potential lead for new chemotherapy of Chagas' disease.
journal_name
Mol Biochem Parasitoljournal_title
Molecular and biochemical parasitologyauthors
Harth G,Andrews N,Mills AA,Engel JC,Smith R,McKerrow JHdoi
10.1016/0166-6851(93)90086-dsubject
Has Abstractpub_date
1993-03-01 00:00:00pages
17-24issue
1eissn
0166-6851issn
1872-9428pii
0166-6851(93)90086-Djournal_volume
58pub_type
杂志文章abstract::Surface proteins of male and female gametes of Plasmodium gallinaceum were radioiodinated by the lactoperoxidase method, immunoprecipitated with stage specific antisera and separated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Stage specificity of the surface antigens was further studied by competiti...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(84)90061-6
更新日期:1984-04-01 00:00:00
abstract::Given the growing appreciation of serious health sequelae from widespread Trichomonas vaginalis infection, new tools are needed to study the parasite's genetic diversity. To this end we have identified and characterized a panel of 21 microsatellites and six single-copy genes from the T. vaginalis genome, using seven l...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2010.08.006
更新日期:2011-01-01 00:00:00
abstract::The glycosylphosphatidylinositol (GPI)-anchored variant surface glycoprotein (VSG) of Trypanosoma brucei is the most abundant GPI-anchored protein expressed on any cell, and is an essential virulence factor. To determine what structural features affect efficient expression of VSG, we made a series of mutations in two ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(03)00055-0
更新日期:2003-05-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(97)00225-9
更新日期:1998-04-01 00:00:00
abstract::The separation by chromatofocusing of two distinct purine nucleoside cleaving activities from crude extracts of Trypanosoma brucei brucei is described. One catalyzes the reversible phosphorolysis of 5'-deoxy-5'-methylthioadenosine (MeSAdo) and adenosine (Ado) and was designated an MeSAdo/Ado phosphorylase, while the o...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(88)90030-8
更新日期:1988-01-15 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(90)90062-q
更新日期:1990-03-01 00:00:00
abstract::We have cloned and sequenced a homologue of the ring-infected erythrocyte surface antigen (RESA) gene from Plasmodium falciparum designated RESA-2. Two reading frames with high homology to exon 1 and exon 2 of RESA at both the nucleotide and amino acid levels were identified in the RESA-2 sequence. However, RESA-2 doe...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(92)90113-x
更新日期:1992-09-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2006.07.005
更新日期:2006-12-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(89)90107-2
更新日期:1989-11-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(99)00190-5
更新日期:2000-02-05 00:00:00
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pub_type: 杂志文章
doi:10.1016/0166-6851(82)90035-4
更新日期:1982-05-01 00:00:00
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pub_type: 杂志文章
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更新日期:2016-06-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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更新日期:2011-02-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2005.09.007
更新日期:2006-01-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(80)90002-x
更新日期:1980-04-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(93)90107-9
更新日期:1993-12-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(88)90153-3
更新日期:1988-12-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(91)90070-m
更新日期:1991-12-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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更新日期:1993-11-01 00:00:00
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pub_type: 杂志文章
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更新日期:1986-01-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2007.01.010
更新日期:2007-05-01 00:00:00
abstract::A total of 518 expressed sequence tags (ESTs) have been generated from clones randomly selected from a cDNA library and a spliced leader sub-library of a Trypanosoma brucei rhodesiense bloodstream clone. 205 (39%) of the clones were identified based on matches to 113 unique genes in the public databases. Of these, 71 ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(95)00098-l
更新日期:1995-07-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2010.10.005
更新日期:2011-02-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2016.09.002
更新日期:2017-01-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2012.04.006
更新日期:2012-07-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(98)00170-4
更新日期:1999-01-25 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(86)90127-1
更新日期:1986-12-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2014.04.003
更新日期:2014-03-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2004.03.004
更新日期:2004-07-01 00:00:00
abstract::Schistosomes have a complex life cycle (vertebrate and molluscan hosts as well as larvae living freely in water) in which they are exposed to different environments and temperatures (20 degrees C - 37 degrees C). Since heat shock genes are activated in response to stress and during development [1], it is of interest t...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(92)90188-p
更新日期:1992-12-01 00:00:00