Abstract:
:The beta subunits (beta1, beta2, and beta5) of 20S proteasome and HslV/ClpQ are ATP-dependent threonine proteases present in eukaryotes and prokaryotes, respectively that control levels of key regulatory proteins in the cell. The orthologue of prokaryotic HslV protease in Plasmodium falciparum (PfHslV) is a novel drug target candidate that has no homolog in the human host. In the present study, the PfHslV was expressed, localized and biochemically characterized. The recombinant PfHslV harbored threonine protease specific activity as well as chymotrypsin like and peptidyl glutamyl peptide hydrolase activities. All the three activities could be inhibited by respective specific inhibitors. The protein was localized in the cytosol of the parasite as a soluble protein by Western immunoblotting of parasite fractions and by immuno-fluorescence microscopy. Activity of the protease in the parasite was ascertained by following the degradation of GFP in a transgenic parasite line expressing fusion protein of GFP and Arc-repressor gene, a known target of HslV protease in the prokaryotes. A model structure of PfHslV was constructed based on the crystal structure of Escherichia coli HslV to assess the structural homology. Availability of the structure model of PfHslV may facilitate identification or designing of novel and specific drugs against PfHslV. The in vitro protease assays with recombinant PfHslV and the transgenic parasite line generated in the present study may be exploited in the screening of novel inhibitors to evaluate their anti-malarial activity.
journal_name
Mol Biochem Parasitoljournal_title
Molecular and biochemical parasitologyauthors
Ramasamy G,Gupta D,Mohmmed A,Chauhan VSdoi
10.1016/j.molbiopara.2007.01.002subject
Has Abstractpub_date
2007-04-01 00:00:00pages
139-48issue
2eissn
0166-6851issn
1872-9428pii
S0166-6851(07)00014-Xjournal_volume
152pub_type
杂志文章abstract::Even at the present age of whole-organism analysis, e.g., genomics, transcriptomics, and proteomics, the biological roles of many proteins remain unresolved. Classified among the proteins of unknown function is a family of proteins harboring repeats of the DM9 domain, a 60-75 amino acids motif first described in a sma...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2016.02.008
更新日期:2016-01-01 00:00:00
abstract::We have purified and characterized the Ascaris suum gamma-glutamylcysteine synthetase, the rate-limiting step in the glutathione biosynthesis. The purified enzyme exhibited a specific activity of 18 U (mg protein)-1. Estimation of the molecular mass of the native enzyme by FPLC on Superdex S-200 revealed the presence ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(94)00064-t
更新日期:1995-06-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2017.09.003
更新日期:2017-12-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(94)00156-1
更新日期:1994-11-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(03)00119-1
更新日期:2003-07-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(00)00292-9
更新日期:2000-10-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/0166-6851(82)90023-8
更新日期:1982-12-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/s0166-6851(99)00110-3
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
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更新日期:1989-02-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/0166-6851(91)90070-m
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章,评审
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更新日期:2008-02-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/0166-6851(88)90061-8
更新日期:1988-03-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(95)00120-p
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:10.1016/0166-6851(92)90152-a
更新日期:1992-11-01 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)90202-8
更新日期:1989-08-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(01)00441-8
更新日期:2002-03-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(94)90030-2
更新日期:1994-07-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(90)90062-q
更新日期:1990-03-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(87)90064-8
更新日期:1987-01-02 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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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2010.06.005
更新日期:2010-11-01 00:00:00
abstract::An adenine nucleoside phosphorylase (ANP, EC none) activity was identified and partially purified from extracts of Schistosoma mansoni by chromatofocussing column chromatography and molecular sieving. The enzyme is distinct from purine nucleoside phosphorylase (PNP, EC 2.4.2.1). ANP is specific for adenine nucleosides...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2014.04.008
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/s0166-6851(97)00068-6
更新日期:1997-08-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(92)90072-r
更新日期:1992-04-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(85)90045-3
更新日期:1985-06-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2007.07.010
更新日期:2007-11-01 00:00:00
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journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章,评审
doi:10.1016/j.molbiopara.2008.04.006
更新日期:2008-08-01 00:00:00
abstract::Malaria parasites possess a de novo heme synthetic pathway. Interestingly, this pathway is dispensable during the blood stages of development in mammalian hosts. The assembly of the two most important hemeproteins, cytochromes c and c1, is mediated by cytochrome heme lyase enzymes. Plasmodium spp. possess two cytochro...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2016.08.003
更新日期:2016-01-01 00:00:00
abstract::Schistosomiasis remains a severe problem of public health in developing countries. Several reports show that praziquantel, the drug of choice for treating schistosomiasis, can select Schistosoma mansoni strains resistant to the drug. Thus, developing new drugs against this parasitosis is a highly desirable goal. Curcu...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2012.11.006
更新日期:2013-02-01 00:00:00
abstract::We have investigated the protein and glycoprotein content of Plasmodium falciparum merozoites by metabolically labeling cultures of schizont-stage parasites with [35S]methionine or with [3H]glucosamine followed by incubation in nonradioactive medium to allow the schizonts to mature into merozoites, infect new erythroc...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(84)90030-6
更新日期:1984-03-01 00:00:00