Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sm25 is the principal antigen recognised by antibodies from mice protectively vaccinated with isolated tegumental membranes of adult Schistosoma mansoni. The full-length amino acid sequence of this protein has been deduced from the sequence of two cDNAs, one isolated by screening a cDNA library and the other, including the 5' end of the gene, amplified directly from adult worm RNA using the polymerase chain reaction. The predicted sequence represents a nascent polypeptide of Mr 21,500. Following cleavage of a predicted signal sequence, the Mr of the resulting polypeptide is 17,600. The polypeptide contains 2 potential sites for N-linked glycosylation and a hydrophobic domain at the C-terminus that could facilitate membrane association. Analysis of the mature gene product confirmed that Sm25 is an N-glycosylated integral membrane protein and that the Mr of the deglycosylated polypeptide is between 15,000 and 20,000.
Mol Biochem Parasitol 1991 Apr
PMID:Structure of Sm25, an antigenic integral membrane glycoprotein of adult Schistosoma mansoni. 203 57

Antigen B, a major antigen of the cestode parasite Taenia solium, has been purified and a portion of amino acid sequence obtained. Paramyosin of the trematode parasite Schistosoma mansoni, an immunogenic protein that has shown promise as a vaccine candidate, has several biochemical and immunological properties in common with antigen B. A full-length cDNA clone of S. mansoni paramyosin has been obtained and the predicted translation product contains a sequence that is highly homologous to the sequence obtained for antigen B. The predicted amino acid composition and isolectric point of paramyosin are nearly identical to those established for antigen B. Recombinant S. mansoni paramyosin, expressed in Escherichia coli as a fusion protein with beta-galactosidase, was recognized by antisera against T. solium antigen B. We conclude from these results that S. mansoni paramyosin and T. solium antigen B are homologous proteins. Since S. mansoni paramyosin is thought to be a muscle protein and T. solium antigen B a secreted glycoprotein with anti-complement activity, this conclusion raises some interesting questions regarding the role of this class of proteins in the host-parasite relationship.
Mol Biochem Parasitol 1991 Feb
PMID:Paramyosin is the Schistosoma mansoni (Trematoda) homologue of antigen B from Taenia solium (Cestoda). 205 29

The effect of Ro 15-5458 (10-2-(diethylamino)ethyl-9-acridanone(2-thiazolin- 2-yl)hydrazone) on the steady-state RNA levels of Schistosoma mansoni was studied after dosing the host with 15 mg kg-1 and retrieving parasites. Total RNA content of parasites recovered from the host 12, 72 and 96 h after dosing was reduced by 14, 30 and 41%, respectively. Quantitative filter hybridization of blots of RNA extracted from treated and control parasites with specific probes indicated a decline in actin and superoxide dismutase mRNA as well as rRNA of treated parasites. The decline was observed 12 h after dosing, 48 h before parasites showed drug-induced changes in other vital biological processes. A prominent drug-induced reduction was seen on the 1.9 kb actin mRNA compared to the 1.4 kb. The same dose of the drug did not alter the actin mRNA content of the host liver. Similarly, the administration of the inactive structural analogue Ro 21-6787 (10-2-(diethylamino)ethyl-9-acridanone) was without any effect. We propose that the actions of Ro 15-5458 and/or its products are directed towards the inhibition of the expression of parasite genes.
Mol Biochem Parasitol 1991 Mar
PMID:The schistosomicidal compound Ro 15-5458 causes a reduction in the RNA content of Schistosoma mansoni. 205 31

The activities of aspartate (AST) and alanine (ALT) aminotransferases and that of lactate dehydrogenase (LD) were measured in the homogenate of infected Biomphalaria alexandrina snails, the specific intermediate hosts for the parasite Schistosoma mansoni which is the cause of the disease schistosomiasis. The isoenzymatic pattern of LD was also studied in the infected snails tissue.
Cell Mol Biol 1990
PMID:Measurement of some selected enzymatic activities in infected Biomphalaria alexandrina snails. 208 18

Molecular mimicry has been considered as a possible way for parasites to escape host immune responses. This work concerns the characterization of protein determinants shared by Schistosoma mansoni and its intermediate host Biomphalaria glabrata. Parasite (Sm39) and mollusc (Bg 39) cross-reactive proteins were identified and shown to induce in rabbit and mouse, antibodies specific for invertebrate determinants. Ultrastructural studies demonstrated that antibodies to Sm39 specifically bound to muscular structures of parasite and mollusc. Molecular cloning and sequencing indicated that Bg39 corresponded to a muscular isoform of tropomyosin. The mollusc sequence showed a 51-65% homology with seven different muscular tropomyosins from vertebrate and invertebrate species. The highest score of homology was observed with S. mansoni tropomyosin, suggesting that cross-reactive determinants could be specific for the trematode and its intermediate host. In miracidia, Sm39 epitopes were also shown to be contained in the vesicles present in epidermal ridges and cellular bodies. Such vesicles are involved in the formation of a protective tegument around sporocysts, suggesting a possible role of cross-reactive tropomyosins in miracidia and/or sporocyst-snail interactions.
Mol Biochem Parasitol 1990 Dec
PMID:Structural homology of tropomyosins from the human trematode Schistosoma mansoni and its intermediate host Biomphalaria glabrata. 209 Sep 46

Hamsters infected with Schistosoma mansoni were operated upon to install a permanent canula into their blood stream. After recovery of the hamster, this canula was used for the injection of radioactively labelled glucose. In this way the glycogen metabolism of S. mansoni could be studied while the parasites remained undisturbed in their natural habitat. The consecutive injection of [U-14C]glucose and [1-3H]glucose permitted an analysis of possible changes in the glycogen synthesis of individual worm pairs with time. The results showed that the synthesis of glycogen by each worm pair was fairly constant with time. Furthermore, all individual worm pairs synthesised glycogen continuously; not even 2 min passed without its formation. Only small differences in glycogen synthesis were observed between parasites isolated from different locations in the veins of the hamster. These results exclude the possibility that the worm pairs had alternating periods of glycogen synthesis and degradation, and they also disprove the idea that synthesis and degradation occur at two different sites in the bloodstream of the hamster. The experiments further showed that glycogen synthesis was proportional to the amount of glycogen already present, which in turn was shown to be proportional to the size of the parasite. From this study it can be concluded that the replenishment of the endogenous glycogen reserves of S. mansoni is not induced by a marked decrease in the glycogen levels, but occurs slowly and continuously.
Mol Biochem Parasitol 1990 Mar
PMID:Continuous synthesis of glycogen by individual worm pairs of Schistosoma mansoni inside the veins of the final host. 210 29

After specific chemotherapy, granulomatous fibrosis undergoes a marked reversal in liver of Schistosoma mansoni-infected mice. We have previously shown that this fibrosis reversal was related to a high proportion of the active form of the interstitial collagenase. In vitro, plasmin has been described as a physiological activator of interstitial procollagenase. Moreover, plasmin itself degrades directly matrix components such as proteoglycans and fibronectin. We have thus followed the course of the plasminogen activator, which converts plasminogen zymogen to plasmin, in liver of S. mansoni-infected mice treated with praziquantel, as schistosomicidal drug. It was found that plasminogen activator activity in the liver increases rapidly until 5 days after treatment as compared to nontreated infected mice and then diminishes gradually. Increased plasminogen activator activity appears to be one of initial events leading to this fibrosis reversal.
Cell Mol Biol 1990
PMID:Plasminogen activator activity increases during reversal of hepatic fibrosis in murine schistosomiasis. 211 35

It has been reported previously that some complex-type Asn-linked oligosaccharides contained in glycoproteins synthesized by Schistosoma mansoni adult males contain terminal galactosyl residues. We report here that extracts from S. mansoni adult male and female worms contain a beta 1,4-galactosyltransferase activity that transfers galactose from the donor substrate UDP-galactose to the acceptor substrate N-acetylglucosamine in a beta 1,4-linkage position to form the disaccharide Gal beta 1,4GlcNAc. In this respect the schistosome-derived activity is similar to that commonly found in mammalian tissues. The kinetic properties, however, of the common beta 1,4-galactosyltransferase activity in mammalian tissues are dramatically altered in the presence of the modifier protein alpha-lactalbumin, whereas the beta 1,4-galactosyltransferase activities in adult male and female schistosomes are not altered by this modifier. Overall, our results demonstrate that adult schistosomes contain a beta 1,4-galactosyltransferase activity and that it is unlike that commonly found in mammalian tissues.
Mol Biochem Parasitol 1990 Nov
PMID:Schistosoma mansoni contains a galactosyltransferase activity distinct from that typically found in mammalian cells. 212 77

Metabolic radiolabeling of adult worms of Schistosoma mansoni with [3H]myristic acid has revealed that the fatty acid is incorporated into more than 15 proteins. We have shown that two of these proteins, a 200-kDa glycoprotein known to be exposed on the surface of the adult worm following praziquantel treatment and a 22-kDa glycoprotein that shows an enhanced immune reactivity with sera of vaccinated mice, are anchored to the adult worm membrane via a glycosylphosphatidylinositol (GPI) linkage. Both antigens partitioned preferentially into the detergent phase of Triton X-114 and were susceptible, following immunoaffinity purification, to hydrolysis by phosphatidylinositol-specific phospholipase C (PIPLC) from Bacillus thuringiensis and phospholipase C from Bacillus cereus. Diacylglycerol (DAG) was released following hydrolysis by bacterial PIPLC; however, Trypanosoma brucei GPIPLC failed to release the diacylglycerol from either protein. Treatment with nitrous acid generated phosphatidylinositol (PI) from both proteins, and phospholipase D from rat serum cleaved phosphatidic acid from the 200-kDa protein. Although the functional significance of these GPI-anchored proteins is unknown, their release from the surface of the schistosome may contribute to immune evasion.
Mol Biochem Parasitol 1990 Jan 15
PMID:Identification and characterization of glycosylphosphatidylinositol-linked Schistosoma mansoni adult worm immunogens. 213 72

This study describes the production and characterization of a monoclonal antibody (mAb) against the alkaline phosphatase of Schistosoma mansoni from splenocytes of chronically infected mice. Convenient selection of the mAb was achieved using the catalytic activity of the antigen in a developed enzyme-antigen immunoassay. The mAb was of the IgG1 subclass and it specifically recognized the alkaline phosphatase in adult worm sections by indirect immunofluorescence. Preincubation of the antibody with partially purified adult alkaline phosphatase did not result in inhibition of the enzyme activity and it did not mediate complement-dependent cytotoxicity against mechanically transformed schistosomula in vitro. The mAb was able to immunoprecipitate under reducing conditions a polypeptide of 65 kDa, similar in size to the monomeric subunit of the schistosome enzyme. The specificity of the mAb was assessed by competitive inhibition with antibodies of infected human sera in an immunoadsorption assay. Periodate treatment of the antigen resulted in altered electrophoretic mobility of alkaline phosphatase, which confirmed the presence of carbohydrate in the molecule, but this did not prevent binding by the mAb. Although the use of the mAb in capture assays for detection of circulating alkaline phosphatase in infected host sera was unsuccessful, the production of this antibody confirmed that the enzyme is exposed by adult worms to the host and that it is immunogenic; additionally, a monoclonal probe is available for further characterization of the structure and function of this important parasite surface molecule.
Mol Biochem Parasitol 1990 Apr
PMID:Production of a mouse monoclonal antibody against the alkaline phosphatase of adult Schistosoma mansoni. 216 96


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