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 of two enzyme activity peaks corresponding to molecular masses of 100 and 70 kDa. The higher-molecular-mass component could be dissociated by repeated gel filtration into the 70-kDa protein which is the enzymatically active subunit. The apparent Km values of the A. suum enzyme for L-aminobutyrate, L-cysteine and L-glutamate were 0.31, 0.41 and 0.94 mM, respectively. D,L-Buthionine-S,R-sulfoximine and cystamine showed time-dependent irreversible inhibitory effects on the A. suum enzyme activity with Ki values of 0.05 and 1.11 microM, respectively. The Ki values for the corresponding enzyme from rat kidney with D,L-buthionine-S,R-sulfoximine and cystamine were 7.19 and 22.2 microM, respectively. The time of half-inactivation of the enzyme at infinite concentration of D,L-buthionine-S,R-sulfoximine, tau 50, was determined to be 3.1 and 1.34 min, for the parasite and mammalian enzymes respectively. For cystamine, a tau 50 value of 3.32 min for the A. suum gamma-glutamylcysteine synthetase was determined, while a value of 2 min in case of rat kidney enzyme was found. The A. suum enzyme activity was competitively inhibited by glutathione with a Ki value of 0.11 mM.(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
Mol Biochem Parasitoljournal_title
Molecular and biochemical parasitologyauthors
Hussein AS,Walter RDdoi
10.1016/0166-6851(94)00064-tsubject
Has Abstractpub_date
1995-06-01 00:00:00pages
57-64issue
1-2eissn
0166-6851issn
1872-9428pii
0166-6851(94)00064-Tjournal_volume
72pub_type
杂志文章abstract::Two dimensional electrophoresis has been used to examine protein variation in clones of two Plasmodium falciparum isolates. Variant forms of 12 proteins were detected. Five genetically distinct parasite types were identified in one isolate, and two in the second isolate. Examination of uncloned parasites using this te...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(85)90085-4
更新日期:1985-08-01 00:00:00
abstract::Leishmania parasites cycle between the alimentary tract of a sandfly vector as free-living promastigotes and the acidified phagolysosomes of the vertebrate host macrophage as aflagellated amastigotes. The differentiation process can be mimicked in host-free culture by switching promastigotes (e.g. 25 degrees C, neutra...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2008.12.012
更新日期:2009-05-01 00:00:00
abstract::This study on isolated cercarial bodies demonstrates that the biological transformation from cercaria to schistosomulum and the biochemical transition from an aerobic to an anaerobic energy metabolism are separate processes, which are not necessarily linked. The metabolic transition depends on the external glucose con...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(92)90202-u
更新日期:1992-03-01 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
abstract::Apicomplexa parasites use complex cell cycles to replicate that are not well understood mechanistically. We have established a robust forward genetic strategy to identify the essential components of parasite cell division. Here we describe a novel temperature sensitive Toxoplasma strain, mutant 13-20C2, which growth a...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2011.09.006
更新日期:2012-01-01 00:00:00
abstract::A wide range of secondary biological functions have been documented for eukaryotic aminoacyl-tRNA synthetases including roles in transcriptional regulation, mitochondrial RNA splicing, cell growth, and chemokine-like activities. The asparaginyl-tRNA synthetase (AsnRS) of the filarial nematode, Brugia malayi, is a high...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2012.06.003
更新日期:2012-09-01 00:00:00
abstract::Root-knot nematodes (Meloidogyne spp.) are among the most important plant pathogens. In this study, the mitochondrial (mt) genomes of the root-knot nematodes, M. chitwoodi and M. incognita were sequenced. PCR analyses suggest that both mt genomes are circular, with an estimated size of 19.7 and 18.6-19.1kb, respective...
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
abstract::Over the last years an expanding family of small RNAs (i.e. microRNAs, siRNAs and piRNAs) was recognized as key players in diverse forms of gene silencing and chromatin organization. Effectors functions of these small RNAs are achieved through ribonucleoprotein (RNP) complexes containing at their center an Argonaute/P...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2010.02.003
更新日期:2010-06-01 00:00:00
abstract::Cryptosporidium parvum is a protozoan parasite of the intestinal epithelium that has caused numerous outbreaks of diarrheal illness in humans. During our studies of the host immune response to C. parvum infection, we noted that two of the immunodominant surface antigens of the sporozoite stage of the parasite readily ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(00)00386-8
更新日期:2001-03-01 00:00:00
abstract::Superposition of two unrelated processes, namely terminal reticulocyte differentiation and synchronous plasmodial development, takes place in experimental infections of Plasmodium berghei. The first process is shown to be responsible for the appearance of some discrete restriction bands of host origin when DNA is extr...
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
abstract::Erythrocyte invasion by malaria parasites requires specific receptor-ligand interactions. Plasmodium vivax and Plasmodium knowlesi are completely dependent on binding the Duffy blood group antigen to invade human erythrocytes. P. knowlesi invades rhesus erythrocytes by multiple pathways using the Duffy antigen as well...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(02)00017-8
更新日期:2002-04-30 00:00:00
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::The apicoplast is a highly specialized organelle that mediates required functions in the growth and replication of apicomplexan parasites. Despite structural conservation of the apicoplast among different parasite genera and species, there are also critical differences in the metabolic requirements of different parasi...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2011.10.009
更新日期:2012-02-01 00:00:00
abstract::Representatives of all major lineages of eukaryotes contain peroxisomes with similar morphology and mode of biogenesis, indicating a monophyletic origin of the organelles within the common ancestor of all eukaryotes. Peroxisomes originated from the endoplasmic reticulum, but despite a common origin and shared morpholo...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章,评审
doi:10.1016/j.molbiopara.2016.02.005
更新日期:2016-01-01 00:00:00
abstract::Glutathione S-transferases (GSTs) constitute a major detoxification mechanism in helminth organisms and are regarded vaccine candidates against helminth infections. Onchocerca volvulus glutathione-binding proteins were purified from the aqueous soluble fraction of homogenised adult females by affinity chromatography o...
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
abstract::Cystic echinococcosis in humans and livestock animals is caused by infection with the cestode parasite Echinococcus granulosus. A number of genotypes of the parasite (designated G1-G10) are known to exist, with the genotype cluster G1-G3 and genotype G6 being responsible for the majority of humans infections. A recomb...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2012.02.005
更新日期:2012-06-01 00:00:00
abstract::Apicomplexan parasites utilize a peripheral membrane system called the inner membrane complex (IMC) to facilitate host cell invasion and parasite replication. We recently identified a novel family of Toxoplasma IMC Sub-compartment Proteins (ISP1/2/3) that localize to sub-domains of the IMC using a targeting mechanism ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2012.05.002
更新日期:2012-08-01 00:00:00
abstract::The infective larval stage of the nematode Trichinella spiralis is an intracellular parasite of skeletal muscle cells. Infection with T. spiralis results in dedifferentiation of the host cell and the formation of a host/parasite complex. A gene encoding a T. spiralis Helix-Loop-helix (HLH) protein with homology to the...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(96)02673-4
更新日期:1996-10-30 00:00:00
abstract::A Babesia bovis merozoite protein, Bb-1, was localized by immunoelectron microscopy to an apical organelle known as the spherical body. This unique structure appears to be analogous to dense granules of other apicomplexan protozoa. Similar to previously described dense granule proteins of Plasmodium spp., Bb-1 is secr...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(94)00200-7
更新日期:1995-02-01 00:00:00
abstract::Genetic diversity within and between tandemly arrayed copies of the Gp63 gene occurs in laboratory isolates of Leishmania spp., but the extent to which this represents natural genetic diversity has not been assessed. Here, the Gp63 locus is examined in 58 fresh isolates of L. peruviana, and clones derived from them, c...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(95)00079-g
更新日期:1995-06-01 00:00:00
abstract::The microtubular cytoskeleton of most single-celled eukaryotes radiates from an organizing center called the flagellar apparatus, which is essential for locomotion, feeding and reproduction. The structure of the flagellar apparatus tends to be conserved within diverse clades of eukaryotes, and modifications of this ov...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章,评审
doi:10.1016/j.molbiopara.2016.02.002
更新日期:2016-01-01 00:00:00
abstract::Kinetoplast DNA (kDNA), the mitochondrial DNA of trypanosomes, is a network of thousands of topologically interlocked DNA minicircles and about 50 maxicircles. In this study, we have analysed the kDNA molecules of 6 strains of Trypanosoma evansi from different geographical areas. 2 strains were found to be dyskinetopl...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(91)90203-i
更新日期:1991-05-01 00:00:00
abstract::Opisthorchis viverrini is the causative agent of human opisthorchiasis in Thailand and long lasting infection with the parasite has been correlated with the development of cholangiocarcinoma. In this work we have molecularly characterized the first member of a protein family carrying two DM9 repeats in this parasite (...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2016.04.002
更新日期:2016-05-01 00:00:00
abstract::The glycoproteins of 12-28 kD from Taenia solium metacestodes provide a high specificity and sensitivity for the serological diagnosis of the central nervous system infection, neurocysticercosis. Their widespread use as antigens for routine serological assays will require their production in large and reproducible amo...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(01)00256-0
更新日期:2001-05-01 00:00:00
abstract::Glycosomes are peroxisome-like organelles present in trypanosomatid pathogens. These organelles compartmentalize glycolysis, among other reactions, and are essential in both bloodstream and procyclic form Trypanosoma brucei. Peroxins (PEXs) are proteins necessary for biogenesis of peroxisomes and glycosomes. In each a...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2005.03.008
更新日期:2005-07-01 00:00:00
abstract::The influence of pH on the activity of purified pyruvate kinase (ATP:pyruvate 2-O-phosphotransferase, EC 2.7.1.40) from Trypanosoma brucei has been studied. The Km for the coenzyme ADP is pH-dependent and shows the involvement of a dissociable group on the free enzyme with a pKa of 6.5-6.7. The cooperative interaction...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(81)90032-3
更新日期:1981-11-01 00:00:00
abstract::Plasmodium falciparum is the causative organism for the most severe form of malaria among humans. The clinical symptoms are accredited to the asexual stage of parasite life cycle, involving merozoite invasion of erythrocyte, development and re-invasion into the new erythrocyte. Interaction of parasite proteins present...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2015.09.004
更新日期:2015-08-01 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 DNA contents of three different Trypanosoma cruzi strains were compared by direct microfluorometry. The maximal difference found was 40% of the lowest value. Two of the cloned strains, reported in an earlier study to differ by 48% in their total DNA content, showed a difference of 33%. The kinetoplast of the Y str...
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
abstract::A Trypanosoma cruzi small subunit ribosomal RNA gene was sequenced from genomic recombinant plasmid clones. The assigned coding region was 2319 bp, the longest SSU rRNA gene described to date. On the basis of comparisons with published sequences from Crithidia fasciculata, Trypanosoma brucei, and Leishmania donovani, ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(90)90183-m
更新日期:1990-06-01 00:00:00