Abstract:
:Recent investigations into quinoline and phenanthrene methanol resistance in Plasmodium falciparum have described a linkage between amplification of the mdr homologue pfmdr1 and decreased susceptibility to mefloquine (MQ) and halofantrine (HF). We have examined the current theories on cross-resistance patterns and pfmdr1 gene expression by comparing the chloroquine (CQ) resistant isolate K1 with K1Hf, developed from the K1 isolate by intermittent exposure to halofantrine. Reduced halofantrine susceptibility in K1Hf was accompanied by reduced sensitivity to mefloquine and increased sensitivity to chloroquine. These sensitivity changes were reflected by changes in parasite drug accumulation. The loss of high level chloroquine resistance in K1Hf was associated with an inability of verapamil to enhance chloroquine sensitivity or accumulation. In contrast verapamil retained the chemosensitising potential against quinine in this isolate. The changes in phenotype were achieved without any amplification or increased expression of pfmdr1 or reversion of the Tyr86 mutation in the gene. Our data indicates that acquisition of halofantrine and mefloquine resistance and the loss of high level chloroquine resistance can be achieved without enhanced expression of the pfmdr1 gene product.
journal_name
Mol Biochem Parasitoljournal_title
Molecular and biochemical parasitologyauthors
Ritchie GY,Mungthin M,Green JE,Bray PG,Hawley SR,Ward SAdoi
10.1016/s0166-6851(96)02746-6subject
Has Abstractpub_date
1996-12-02 00:00:00pages
35-46issue
1eissn
0166-6851issn
1872-9428pii
S0166685196027466journal_volume
83pub_type
杂志文章abstract::The interaction of Leishmania promastigote surface protease (PSP) with the plasmatic protease inhibitor alpha 2-macroglobulin (alpha 2M) was investigated. In plasma, solubilized PSP forms covalent complexes only with alpha 2M, at the exclusion of other protease inhibitors. The formation of complexes is accompanied by ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(89)90043-1
更新日期:1989-02-01 00:00:00
abstract::Three days after mice were inoculated with Trypanosoma brucei gambiense, total hepatic cytochrome P-450 levels were decreased 14% from control values, while the specific mixed-function oxidase activity (per nmole of cytochrome P-450) was inhibited almost 40% in infected animals. Furthermore, drugs used to treat trypan...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(81)90051-7
更新日期:1981-08-01 00:00:00
abstract::Surface membrane proteins of viable merozoites of Plasmodium chabaudi were iodinated by the Iodogen method and analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Thirteen surface membrane proteins ranging from 22 to 270 kDa were thus identified. Most of these proteins could be immunoprecipitated by...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(84)90014-8
更新日期:1984-01-01 00:00:00
abstract::Cystic hydatid disease (CHD) is caused by infection with Echinococcus granulosus metacestodes and affects humans and livestock. Proteins secreted or excreted by protoscoleces, pre-adult worms found in the metacestode, are thought to play fundamental roles in the host-parasite relationship. In this work, we performed a...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2012.01.001
更新日期:2012-05-01 00:00:00
abstract::The nucleotide sequence of two non-contiguous DNA fragments of 4.0 and 2.2 kb, respectively, of the kinetoplast maxicircle of Trypanosoma brucei brucei EATRO strain 427 has been determined, completing the sequence analysis of the so-called variable region (see also de Vries et al., 1988, Mol. Biochem. Parasitol. 27, 7...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(92)90178-m
更新日期:1992-12-01 00:00:00
abstract::Helicases are ubiquitous essential enzymes which have significant role in the nucleic acid metabolism. Using in silico approaches in the recent past we have identified a number of helicases in the Plasmodium falciparum genome. In the present study we report purification and detailed characterization of a novel helicas...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2010.12.003
更新日期:2011-03-01 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::Acetylcholinesterase (AChE) plays a key role in postsynaptic transmission in most animals. Nematodes encode multiple AChEs, implying its functional diversity. To explore physiological functions of multiple AChEs, three distinct AChEs (BxACE-1, BxACE-2, and BxACE-3) were identified and characterized from the pinewood n...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2010.11.005
更新日期:2011-02-01 00:00:00
abstract::The synchronization of intraerythrocytic maturation of Plasmodium parasites is an important factor in the malaria infection process. Synchronization is mediated by inositol phosphate (InsP(x))-induced Ca(2+)-release from internal stores. To further investigate the InsP(x) metabolism in these parasites a Plasmodium pro...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2012.10.005
更新日期:2012-12-01 00:00:00
abstract::Tubulin-binding cofactor C stimulates GTPase activity and contributes to the release of the heterodimeric α/β-tubulin from a super-complex of tubulin monomers and two ancillary cofactors. We have determined the 2.2 Å resolution crystal structure of the C-terminal domain of tubulin-binding cofactor C from Leishmania ma...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2015.05.003
更新日期:2015-05-01 00:00:00
abstract::With the rapid spread of drug-resistant strains of Plasmodium falciparum, the development of new antimalarials is an urgent need. As malaria parasites live in a highly pro-oxidant environment, their anti-oxidant defences have frequently been suggested as candidate drug targets. A key point in such defences is the prod...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2010.04.002
更新日期:2010-08-01 00:00:00
abstract::The precursor of the glycosylphosphatidylinositol membrane anchor of the variant surface glycoprotein of Trypanosoma brucei is known as glycolipid A and it has the structure: EtN-PO4-6Man alpha 1-2Man alpha 1-6Man alpha 1-4GlcN alpha 1-6myo-inositol-PO4-(sn-1,2-dimyristoylglycerol). This precursor exists in equilibriu...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(96)02585-6
更新日期:1996-05-01 00:00:00
abstract::Protein kinase activities in bloodstream and procyclic forms of Trypanosoma brucei have been partially purified and characterised. Cytosolic extracts were separated on DEAE-cellulose and assayed for the ability to phosphorylate histone in the presence of Ca2+ and diacylglycerol. Five peaks of activity were identified ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(90)90135-9
更新日期:1990-11-01 00:00:00
abstract::The mature-parasite-infected erythrocyte surface antigen (MESA, also known as PfEMP-2 and pp300) of Plasmodium falciparum is a phosphoprotein of approx. 250-300 kDa that is exported from the parasite to the erythrocyte membrane skeleton where it binds to protein 4.1. Determination of the primary sequence of MESA revea...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(92)90231-8
更新日期:1992-02-01 00:00:00
abstract::Leucine aminopeptidases (LAP; EC 3.4.11.1) are a group of metalloexopeptidases, which catalyze the sequential removal of leucine amino acids from the N-termini of the polypeptides or proteins. In this study, we identified two novel genes that encode LAPs of Clonorchis sinensis (CsLAP1 and CsLAP2) and characterized the...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2011.11.009
更新日期:2012-03-01 00:00:00
abstract::The obligate intracellular protozoan parasite Toxoplasma gondii has a single tubular mitochondrion. During infection, it recruits the host cell's mitochondria abutting to the intracellular vacuole, that contains the parasites. The respective contribution of host and parasitic mitochondria in the intracellular growth o...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(00)00324-8
更新日期:2000-12-01 00:00:00
abstract::Toxocariasis is a neglected disease, and its main etiological agent is the nematode Toxocara canis. Serological diagnosis is performed by an enzyme-linked immunosorbent assay using T. canis excretory and secretory (TES) antigens produced by in vitro cultivation of larvae. Identification of TES proteins can be useful f...
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
abstract::Trypanosoma brucei is a unicellular parasite that is transmitted from one mammalian host to the next by tsetse flies. The expression of many trypanosome genes is regulated during the life cycle but there is no evidence for developmental control of transcription by RNA polymerase II. T. brucei expresses at least two he...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(95)02503-0
更新日期:1995-12-01 00:00:00
abstract::The Giardia lamblia genome consists of 12 Mb divided among 5 chromosomes ranging in size from approximately 1 to 4 Mb. The assembled contigs of the genotype A1 isolate, WB, were previously mapped along the 5 chromosomes on the basis of hybridization of plasmid clones representing the contigs to chromosomes separated b...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2011.07.008
更新日期:2011-12-01 00:00:00
abstract::Surface labeling studies using two populations of Onchocerca gibsoni microfilariae revealed important differences in major radioiodinated proteins. Small numbers of microfilariae harvested from the skin of cattle or the uteri of adult worms from skin nodules were purified, radioiodinated, solubilized and the proteins ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(84)90009-4
更新日期:1984-02-01 00:00:00
abstract::Theileria annulata is an important pathogen of cattle in the tropics. The gene sequence of a sporozoite surface antigen (SPAG-1) is reported. Data is also presented demonstrating that SPAG-1 is synthesised as a large precursor. This antigen, which is a candidate for inclusion in a subunit vaccine, shows a remarkable d...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(92)90012-9
更新日期:1992-07-01 00:00:00
abstract::A polyprotein composed of multiple units arranged in direct tandem arrays has been identified in parasitic and free living nematodes. Analysis of previously cloned units from the Dirofilaria immitis polyprotein antigen (DiPA) indicated the units were nearly identical but here we demonstrate that they segregate into tw...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(96)02721-1
更新日期:1996-11-12 00:00:00
abstract::The guide RNA (gRNA) paradigm states that the uridine (U) insertion/deletion type of RNA editing is mediated by short 3' uridylylated gRNAs that are complementary to specific blocks of mature edited sequence. These gRNAs contain the edited sequence information in the form of guiding purine residues that can base pair ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章,评审
doi:10.1016/s0166-6851(97)00037-6
更新日期:1997-06-01 00:00:00
abstract::Following the demonstration that the transport of melaminophenyl arsenical drugs in Trypanosoma brucei is dependent upon an unusual adenosine nucleoside transporter (Carter and Fairlamb, Nature 361 (1993) 173-175) we have investigated adenosine transport in the related parasite Trypanosoma equiperdum (Botat1.1) and a ...
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
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 hyb...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(91)90132-p
更新日期:1991-11-01 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::Mitochondrial ATPase of Leishmania donovani was characterized using digitonin-permeabilized promastigotes and the results were compared with those from isolated mitochondria. Maximum mitochondrial ATPase activity was obtained in promastigotes permeabilized with digitonin at a final concentration of 20 microM and the s...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(93)90140-s
更新日期:1993-08-01 00:00:00
abstract::Among several protease inhibitors tested, only leupeptin was found to modify qualitatively the processing of P126, a major antigen of the parasitophorous vacuole of Plasmodium falciparum, and to inhibit the release of merozoites. Whereas P126 is normally processed upon merozoite release into 2 polypeptides of 50 and 7...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(89)90029-7
更新日期:1989-03-01 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::Entamoeba histolytica is responsible for amoebic colitis and liver abscess in humans. Entamoeba dispar is a closely related, morphologically indistinguishable nonpathogenic species. The hexokinase (ATP:D-hexose 6-phosphotransferase, EC 2.7.1.1) isoenzyme patterns distinguish the pathogenic and nonpathogenic species. B...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(99)00164-4
更新日期:2000-01-05 00:00:00