Abstract:
:A family of Schistosoma mansoni proteins (18-22 kDa, pI 5.3-5.8) are biosynthesized in juvenile worms and immunoprecipitated by antibodies uniquely present in protective Fischer rat antiserum. A cDNA clone, lambda gt11-40, expressing epitopes common to this protein family was used to obtain a genomic DNA clone, by hybridization with a lambda gt11-40 oligonucleotide probe. In the 1.37 kb of genomic DNA sequenced, an open reading frame of 182 amino acids was identified on the strand corresponding to lambda gt11-40 coding sequences, and those of identical independently isolated cDNA clones defining a 25-kDa surface membrane glycoprotein. The new S. mansoni gene is termed GP22. There are two candidate promoters, confirmed by primer extension studies with worm RNA. Promoter 1 (P1) is preceded by a G + C-rich region and potential CAAT sequences, and is to the 5'-side of P2. Transcription from P1 is initiated at 2 different sites, apparently producing mRNAs with different translation start sites (ATG). Decoding these mRNAs yields protein products of 182 (P1), 175 (P1), 140 (P2) and 136 (P2) amino acids. The polypeptides share the following features: a hydrophobic segment near the carboxy terminus sufficient to span a lipid bilayer, with a consensus sequence for thio-esterification by a fatty acid; an external domain containing 2 potential N-linked glycosylation sites; and a candidate leucine-zipper motif, suggesting the protein may exist as a dimer on the worm surface. While sharing these common features in their carboxy terminal regions, the three proteins differ in the length and properties of their amino termini. The 140-amino acid protein has a short hydrophobic amino terminus, while the 175- and 182-amino acid proteins have more extensive hydrophobic sequences, each preceded by a hydrophilic amino terminal sequence. The heterogeneity observed in 2-dimensional gels of the antigen may be explained in part by the size and charge differences among the proteins deduced from the sequence and transcription pattern of this gene. The possibility of stage-specific regulated expression of this candidate vaccine antigen family is an attractive concept, potentially accounting for the phenomenon of concomitant immunity observed in the rat and perhaps other schistosome hosts.
journal_name
Mol Biochem Parasitoljournal_title
Molecular and biochemical parasitologyauthors
el-Sherbeini M,Ramadan N,Bostian KA,Knopf PMdoi
10.1016/0166-6851(91)90132-psubject
Has Abstractpub_date
1991-11-01 00:00:00pages
83-98issue
1eissn
0166-6851issn
1872-9428pii
0166-6851(91)90132-Pjournal_volume
49pub_type
杂志文章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::A gene-family, named sep, encoding small exported proteins conserved across Plasmodium species has been identified. SEP proteins (13-16 kDa) contain a predicted signal peptide at the NH(2)-terminus, an internal hydrophobic region and a polymorphic, low-complexity region at the carboxy-terminus. One member of the Plasm...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(02)00275-x
更新日期:2003-02-01 00:00:00
abstract::We have generated 2771 expressed sequence tags (ESTs) from two cDNA libraries of Trypanosoma cruzi CL-Brener. The libraries were constructed from trypomastigote and amastigotes, using a spliced leader primer to synthesize the cDNA second strand, thus selecting for full-length cDNAs. Since the libraries were not normal...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2004.04.002
更新日期:2004-08-01 00:00:00
abstract::The variant surface glycoproteins (VSGs) of both metacyclic and bloodstream forms of Trypanosoma congolense are shown to be anchored to the plasma membrane through a glycolipid similar to that found in Trypanosoma brucei. Release of soluble VSG from both metacyclic and bloodstream forms is associated with the exposure...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(87)90045-4
更新日期:1987-01-15 00:00:00
abstract::The ADHE family of enzymes are bifunctional acetaldehyde dehydrogenase (ALDH)/alcohol dehydrogenase (ADH) enzymes that probably arose from the fusion of genes encoding separate ALDH and ADH enzymes. Here we have used the Entamoeba histolytica alcohol dehydrogenase 2 (EhADH2) enzyme as a prototype to analyze the struct...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2004.06.002
更新日期:2004-10-01 00:00:00
abstract::The effect of 9 monosaccharides which constitute cell surface carbohydrates on the infection of bovine embryonic skin and muscle (BESM) cells by Trypanosoma cruzi trypomastigotes and Toxoplasma gondii tachyzoites was assayed. Most of the monosaccharides tested stimulated the infection of BESM cells by T. gondii; none ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(82)90040-8
更新日期:1982-05-01 00:00:00
abstract::A strain of Plasmodium berghei (NK 65) was followed during syringe transmission in mice for over 120 passages after the last complete cycle, while the following parameters were monitored: (a) capacity to infect mosquitoes, inducing oocyst formation; (b) presence in the peripheral blood of morphologically identifiable ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(82)90048-2
更新日期:1982-07-01 00:00:00
abstract::The gender of cercarial larvae can only be determined using molecular methods. End point PCR methods that amplify repetitive markers on the W chromosome of the female (ZW) parasites have been developed, but sometimes results are ambiguous or incorrect. To more effectively distinguish sexes, and to determine why end po...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2016.03.010
更新日期:2016-01-01 00:00:00
abstract::Plasmodium falciparum merozoites invade erythrocytes using a range of alternative ligands that includes erythrocyte binding antigenic proteins (EBAs) and reticulocyte binding protein homologues (Rh). Variation in the expression of some of these genes among culture-adapted parasite lines correlates with the use of diff...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2006.05.014
更新日期:2006-10-01 00:00:00
abstract::The enzyme pterin-4a-carbinolamine dehydratase (PCD) is important for the recycling of pterins within eukaryotic cells. A recombinant expression system for PCD from the apicomplexan parasite Toxoplasma gondii has been prepared, the protein purified and crystallised. Single crystal X-ray diffraction methods have produc...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2007.12.002
更新日期:2008-04-01 00:00:00
abstract::Kinetoplast DNA (kDNA) was isolated from 56 stocks of Trypanosoma cruzi isolated from human patients, animals and insects from Brazil, Venezuela, Colombia and Costa Rica. Comparison of the patterns of digested kDNA on acrylamide gels led to the grouping of several stocks into two schizodemes. Schizodeme analysis was a...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(90)90160-n
更新日期:1990-09-01 00:00:00
abstract::This study is the first demonstration of individual gene products synthesized by Hymenolepis diminuta. To identify proteins synthesized specifically by H. diminuta, we radiolabeled adult worms with [14C]leucine in vitro. Subsequent one- and two-dimensional gel electrophoretic separation and staining of the protein con...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(82)90051-2
更新日期:1982-07-01 00:00:00
abstract::Natural antisense transcripts (NATs) are non-protein coding RNAs that could play an important role in regulating the expression of their counterpart protein encoding sense transcript. Although NATs are widespread in most eukaryotic genomes, very little is known about their functions. This study focuses on gaining a be...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2020.111334
更新日期:2020-11-01 00:00:00
abstract::The merozoite surface protein-1 of the human malaria parasite Plasmodium falciparum undergoes an extracellular proteolytic cleavage (secondary processing) intrinsic to successful erythrocyte invasion. In the T9/96 clone of P. falciparum the protease responsible has been characterised as a membrane-associated, calcium-...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(93)90182-w
更新日期:1993-11-01 00:00:00
abstract::Pathogens of the Leishmania and Trypanosoma genera compartmentalize glycolytic and other nutritional pathways in glycosomes, unique subcellular organelles related to the peroxisomes of mammals and yeasts. Most glycosomal proteins are targeted to the glycosomes by a COOH-terminal tripeptide signal similar to the peroxi...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(02)00164-0
更新日期:2002-09-01 00:00:00
abstract::As an intracellular parasite, Trypanosoma cruzi is exposed to reactive oxygen species. The study of the proteins involved in the hydroperoxide detoxification cascade, tryparedoxin peroxidase included, may lead to the development of a more specific chemotherapy for Chagas'disease. In this work, the involvement of TcCPX...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2003.08.011
更新日期:2004-01-01 00:00:00
abstract::Trophozoites of Entamoeba invadens were able to ingest glucopolysaccharides and metabolize them. An activity capable of degrading these substrates was purified to apparent homogeneity. The enzyme was identified as beta-amylase (alpha-1,4-D-glucan maltohydrolase EC 3.2.1.2): It was active against glycogen, amylose and ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(96)02765-x
更新日期:1996-12-20 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::Theileria parva is a tick-transmitted intracellular protozoan parasite that causes East Coast fever, a fatal bovine lymphoproliferative disease. The molecular mechanisms that underlie host cell transformation by T. parva schizonts have been studied extensively, and it is known that the nuclear factor-kappa B (NF-kappa...
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::Steroids and retinoids are important regulators of development in invertebrates and vertebrates. The central mediators of action of these compounds are their cognate receptors, which together form a family of proteins known as the nuclear receptor family. Previous studies have demonstrated that the genome of Onchocerc...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(99)00152-8
更新日期:1999-11-30 00:00:00
abstract::cDNA clones encoding 473 amino acids of the knob-associated histidine-rich protein (PfHRPI) of Plasmodium falciparum clone FCR-3/A2 (Gambia) have been isolated and sequenced. Although a short region close to the amino terminus of the predicted sequence contains three blocks of six, seven or nine consecutive histidine ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(87)90144-7
更新日期:1987-11-01 00:00:00
abstract::Telomeric DNA of trypanosomatids possesses a modified thymine base, called base J, that is synthesized in a two-step process; the base is hydroxylated by a thymidine hydroxylase forming hydroxymethyluracil (hmU) and a glucose moiety is then attached by the J-associated glucosyltransferase (JGT). To examine the importa...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2016.01.005
更新日期:2015-12-01 00:00:00
abstract::Procyclic Trypanosoma brucei brucei strain 366D is susceptible to DL-alpha-difluoromethylornithine (DFMO) with an in vitro ED50 value of 225 microM. A mutant of the procyclic strain resistant to 20 mM of DFMO was isolated by serial in vitro passages of the organisms in increasing concentrations of the drug. Drug resis...
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
abstract::Genetic transformation of malaria parasites has been limited by the number of selectable markers available. For the rodent malaria parasite, Plasmodium berghei, only a single selection marker has been at hand, utilising the dihydrofolate reductase-thymidylate synthase gene from either P. berghei or Toxoplasma gondii t...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(99)00189-9
更新日期:2000-03-05 00:00:00
abstract::The 31P NMR spectrum of the adult tapeworm, Hymenolepis diminuta, at 37 degrees C during perfusion with physiological saline was composed of 10 peaks. Based on chemical shifts and analysis of worm extracts, the phosphorus components included glucose-6-phosphate, fructose-6-phosphate, phosphorylcholine, glycerophosphor...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(87)90068-5
更新日期:1987-01-02 00:00:00
abstract::The spontaneous emission of chemiluminescence by Trypanosoma cruzi epimastigotes was 133 +/- 5 counts s-1 (mg protein)-1. The measured intracellular steady state concentration of hydrogen peroxide in the same cells was 1.5 +/- 0.5 microM. These two values are about 12- and 15-times higher than the corresponding ones f...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(88)90093-x
更新日期:1988-09-01 00:00:00
abstract::We have demonstrated that bradyzoites return to the tissue-cyst stage by a developmental pathway that is indistinguishable from that initiated by sporozoites. Mature bradyzoites, like sporozoites from oocysts, were non-proliferative as they contained uniform 1N DNA contents, and replication occurred only in parasites ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(03)00198-1
更新日期:2003-10-01 00:00:00
abstract::Chloroquine is a critically important antimalarial drug and a well known intercalator into DNA. We now show that chloroquine binds more avidly to poly(dG-dC).poly(dG-dC) than to other synthetic polynucleotides and that this binding inhibits both salt- and cobalt-induced transitions to Z-DNA. These data are consistent ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(90)90066-u
更新日期:1990-03-01 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::The monosaccharide composition of an affinity-purified family of antigenically-related Trichinella spiralis larval glycoproteins was determined by gas chromatography/mass spectrometry. This group of 6 major glycoproteins, designated TSL-1, originates in the muscle stage (L1) larval stichosome. They are present on the ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(93)90155-q
更新日期:1993-09-01 00:00:00