Showing papers in "Molecular and Biochemical Parasitology in 1991"

TL;DR: Malarial parasites are rich in hemin; artemisinin's reactivity toward hemin may explain its selective toxicity to malarial parasites.

TL;DR: Evolutionary trees inferred from the rRNA sequence similarities support a close phylogenetic relationship between the Apicomplexa and Dinoflagellata as represented by Prorocentrum micans and C. cohnii.

TL;DR: The amino-terminal sequence has been obtained for 2 fragments of the Plasmodium falciparum T9/94 merozoite surface protein precursor and these have been compared with the sequence predicted from the gene and indicate that the C- terminal sequence which is carried into the red cell during invasion consists of 2 epidermal growth factor (EGF)-like domains.

TL;DR: The ribosomal RNA genes of the two forms are quite distinct, which supports the hypothesis that E. histolytica is two species, and has major implications for evaluation and treatment of carriers.

TL;DR: Results indicate that a single T. cruzi cell in 20 ml of blood can be detected by this PCR-based test, and should prove useful as a replacement or complement for xenodiagnosis or serology in clinical and epidemiological studies of chronic Chagas' disease.

TL;DR: In functional assays, gel-purified native 12-kDa antigen from natural infections inhibited elastase but not trypsin or chymotrypsin, providing further evidence that this antigen is a parasite protease inhibitor.

TL;DR: A subcellular fractionation procedure has been established to isolate the rhoptries of Toxoplasma gondii tachyzoites on a self-generating Percoll gradient and major proteins in the organelles are identified by immunoelectron microscopy and Western blotting.

TL;DR: To examine the taxonomic relationships among these morphologically similar organisms, polymerase chain reaction amplification of the small subunit ribosomal RNA gene combined with restriction fragment length polymorphism analysis, 'riboprinting', clearly shows that the 'E. histolytica-like' amoebae are indeed strains of E. moshkovskii, and not closely related to E. histynthia.

TL;DR: The gene encoding a member of the Duffy receptor gene family of P. knowlesi has been cloned and it is reported that this region may act as a 'hinge region' similar to those in the immunoglobulin gene family.

TL;DR: It is suggested that SDEL (carboxy terminal sequence of Pfgrp) might play a similar role in the cellular localization of Pf Grp as does the sequence KDEL in mammalian cells and HDEL in yeast.

TL;DR: It is shown that a soluble 33-kDa polypeptide corresponding to the N-terminal region of MSP1(42) is shed into culture supernatants during merozoite release and erythrocyte invasion, providing further evidence that the secondary processing of M SP1( 42) involves a highly site-specific proteolytic activity.

TL;DR: A gene coding for a 220-kDa glutamate rich protein (GLURP), an exoantigen of Plasmodium falciparum, was isolated and its nucleotide sequence was determined and the deduced amino acid sequence contains 2 repeat regions.

TL;DR: The results show that in a variable region of the ribosomal RNA gene significant variation can be demonstrated between rat-derived and human derived P. carinii.

TL;DR: The degree of polymorphism and the allelic distribution of 2 major Plasmodium falciparum merozoite surface antigens (MSA1 and MSA2) have been analysed in clinical isolates from Colombia and five of these were cloned and their DNA sequenced; these sequences are discussed.

TL;DR: Overall the antigen resembles the thrombospondin-related anonymous protein identified in the erythrocytic stage of Plasmodium falciparum and the structure of the gene supports a role for this microneme antigen in cell-cell or cell-matrix interactions.

TL;DR: A 3.5-kb Sau3AI fragment was cloned from a circular DNA molecule isolated from the human malaria parasite Plasmodium falciparum and found to contain two contiguous open reading frames, suggesting that the circular DNA may be an unusual mitochondrial DNA, or derived from an unidentified organelle.

TL;DR: Genomic and cDNA clones of a gene designated D7, expressed abundantly in the adult female salivary glands of the vector mosquito aegypti, have been isolated and characterized, and indicate that the product is most likely involved with the blood feeding capabilities of the female mosquito.

TL;DR: The malaria parasite Plasmodium falciparum synthesises a protein, RESA, which associates with the membrane of newly invaded erythrocytes, and RESA appears to be associated with spectrin in the ERYthrocyte membrane skeleton.

TL;DR: It is concluded that exp-1 is an integral membrane protein and infer that it is transported by vesicles from the parasite to a compartment in the host cell cytoplasm.

TL;DR: Three microneme proteins of Toxoplasma gondii have been characterized using 3 monoclonal antibodies and a recombinant protein specific antiserum and showed that at least one of the 38-k da polypeptides was processed from a 40-kDa precursor.

TL;DR: Cloning and structural analysis of pBv60 provides a source of defined antigen for determining the role of conserved merozoite surface epitopes in protective immunity against babesiosis.

TL;DR: A cloned 0.64-kb DNA sequence of Schistosoma mansoni contains 121-bp tandem repeats and comprises at least 12% of the schistosomal genome of both sexes and could detect with high sensitivity schistOSomal DNA sequences in infected snails.

TL;DR: It is concluded that the mitochondria of transitional intermediate and short stumpy forms likely produce ATP, contrasting with the previously held dogma that all bloodstream form mitochondria are incapable of ATP production.

TL;DR: The knob protein of Plasmodium falciparum is essential for the formation of knob-like protrusions on the host erythrocyte membrane and a functional domain of the knob protein was identified.

TL;DR: The results indicate that the amastigotes do express a lipophosphoglycan, but that it is structurally distinct from its promastigote counterparts.

TL;DR: Calves immunized with immunoaffinity purified gp45, gp55, or p58 antigens were able to neutralize the infectivity of merozoites as indicated by significant reductions in the peak parasitemia after experimental challenge.

TL;DR: Antigenic variation in the parasitic protozoan Giardia lamblia was studied by characterizing the expression and genomic organization of a variant-specific surface protein (VSP) gene, revealing striking conservation at the nucleotide and amino acid levels, and the 3' ends of the genes.

TL;DR: The expression of a recombinant antigen of 65 kDa and a protein with the same molecular weight was also found in the lysate of E. multilocularis protoscolices and the fusion protein was purified and used for diagnostic purposes in immunoblot.

TL;DR: Isoenzyme analysis and molecular karyotyping of cloned organisms indicated that the putative hybrids are distinct from other species of Leishmania, and possess characteristics of both L. major and L. arabica.