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)

A cDNA library representative of adult Schistosoma mansoni mRNA populations was screened with serum from infected rats (refractory hosts), positive plaques being rescreened with serum from infected mice and humans. Based on general reactivity, one clone was selected for further study. As judged by immunofluorescence data, size of corresponding mRNA, and nucleotide sequence analysis, the recombinant expresses approximately 625 amino acids of a schistosome muscle myosin rod. Antibodies evoked by the protein do not cross-react with human cardiac or skeletal muscle, are not invariably stimulated in naturally infected human beings, and rise in titer after chemotherapeutic cure, findings which suggest that the antigen is not a causative agent of Katayama fever, and is probably presented by degenerating worms. The schistosome sarcomeric myosin gene, the most primitive examined to date, appears to be unique inasmuch as it may not be a member of a multigene family and encodes a single mRNA transcript; nonetheless, predicted higher order structure of its translation product is consistent with expected function.
Mol Biochem Parasitol 1987 Nov
PMID:Molecular cloning of Schistosoma mansoni myosin. 343 65

Both patent and prepatent adult Hymenolepis diminuta excreted 20-hydroxyecdysone into the culture medium when maintained in vitro. Patent worms also excreted ecdysone and comparatively large quantities of unidentified immunoreactive material of a relatively apolar nature. This latter material was shown to be depleted from the endogenous free ecdysteroids of patent adults during the culture period. Ecdysteroid excretion was affected both qualitatively and quantitatively when culturing conditions were varied.
Mol Biochem Parasitol 1987 Dec
PMID:Ecdysteroid excretion by adult Hymenolepis diminuta in vitro. 343 70

A cloned library of DNA complementary to the mRNA of adult Schistosoma japonicum has been prepared and expressed as fusion proteins with Escherichia coli beta-galactosidase. Colonies expressing the S. japonicum cDNA clones were screened both with antibodies from individuals with a history of schistosomiasis and with antibodies obtained from a rabbit immunized with whole adult worms. In both cases colonies were detected which bound antibody, although the frequency of antigen-positive clones was much higher with the rabbit antiserum than with human sera. In both cases the proportion of colonies reacting with antibodies was markedly lower than that published for equivalent screens of Plasmodium falciparum cDNA with sera from individuals with a history of falciparum malaria. Several major S. japonicum antigens were identified by the affinity purification of antibodies using immobilised fusion proteins produced during lytic growth of the recombinant bacteriophage.
Mol Biochem Parasitol 1986 Mar
PMID:Expression of Schistosoma japonicum antigens in Escherichia coli. 351 79

Lipids extracted from whole worm homogenates and tegumental outer membranes of guinea pig-derived 5-day, 2-, 3- and 6-week old schistosomes have been analysed by thin layer chromatography. Six-week hamster-derived parasites have been studied for comparative purposes. All homogenates contained neutral lipids, cholesterol and several phospholipids; phosphatidyl choline and phosphatidyl ethanolamine were major components. Phospholipid (P3) was absent from homogenates of 5-day worms but was present in older parasites. A single phospholipid (P4) which co-chromatographed with phosphatidyl glycerol was unique to hamster-derived parasites. One glycolipid (G1) was ubiquitous to all homogenates and co-chromatographed with the monogalactosyl ceramide marker. A second sugar-containing lipid (G2) was unique to 3-week worm homogenates, and was highly polar. It was resolved beneath the trigalactosyl ceramide marker. Tegumental membranes isolated from 6-week adults contained at least five glycolipids, four of which were also highly polar. Cholesterol and two dominant phospholipids occurred in the membranes of 2-, 3-, and 6-week worms. One phospholipid co-chromatographed with phosphatidyl choline; the other had an Rf value (relative band speed) equivalent to phosphatidyl ethanolamine. Membranes from liver stage parasites contained a further phospholipid which cochromatographed with sphingomyelin, and three additional, phosphate-staining lipids (P1, P3 and P6). Five sugar-containing lipids occurred in adult membranes only; four were highly polar, being resolved near the origin. Similar components were identified in extracts of host erythrocytes. The remaining membrane lipid appeared homologous to G1 identified in the whole worm homogenates. Important changes in lipid composition thus occur during schistosome growth and maturation in guinea pigs; moreover, worms derived from different rodents express different lipids.
Mol Biochem Parasitol 1987 Jan 15
PMID:Analysis of total and surface membrane lipids of Schistosoma mansoni. 357 47

The binding of the plant toxin ricin to various life cycle stages of Schistosoma mansoni has been studied. Fluorescein isothiocyanate (FITC)-ricin exhibited binding to schistosomula and adult worms, but not to cercariae or to freshly transformed schistosomula. Binding was specifically inhibited by the presence of galactose in the medium. Analysis of protein synthesis in treated parasites illustrated that ricin failed to intoxicate schistosomula or adult worms. Indeed, fluorescence quenching studies suggested that the fluorescent toxin was confined to the outer bilayer and was not internalised.
Mol Biochem Parasitol 1987 May
PMID:Interaction of the plant toxin ricin with different life cycle stages of Schistosoma mansoni. 361 73

The human and animal filarial parasites Onchocerca volvulus, Dirofilaria immitis, Brugia patei and Litomosoides carinii contained low levels of putrescine but much higher levels of spermidine and spermine as estimated by ion-pair high pressure liquid chromatography; N-acetylated polyamines were present only in minute amounts. Enzyme activities of ornithine decarboxylase (EC 4.1.1.17) and arginine decarboxylase (EC 4.1.1.19), respectively, were not detectable. Experiments carried out with O. volvulus and D. immitis demonstrated the uptake and bioconversion of labeled polyamines. There is evidence for the existence of a complete reverse pathway generating putrescine from spermidine and spermine, respectively, in both worms. N-Acetylating enzyme activities were detected in 100,000 X g preparations of homogenates from D. immitis which were capable to acetylate putrescine, spermidine and spermine. Long term incubation of the worms in the presence of labeled polyamines resulted in the excretion of putrescine and N-acetylputrescine.
Mol Biochem Parasitol 1987 Jun
PMID:Polyamine metabolism in filarial worms. 362 68

Adult Schistosoma mansoni worms rapidly degrade their endogenous glycogen stores immediately after isolation from the host. In NCTC 109 or in a diphasic culture medium the glycogen levels slowly recovered again after the initial decrease. The rapid degradation of glycogen could be prevented, even in a simple salt medium, if 100 mM glucose and 1% bovine serum albumin were present. Incubations with 14C-labelled glucose under different conditions revealed that the degradation of glycogen was induced by the limited catabolism of external glucose. Conditions are described which induce glycogen degradation or resynthesis by S. mansoni. The physiological function of the glycogen stores is probably to provide substrate during periods of insufficient supply of external glucose. It is speculated that such periods occur when the worm pair moves into the small mesenteric veins of the host. This hypothesis explains the remarkable wandering behaviour of the parasite in the mesenteric veins, since the schistosomes would have to return to larger vessels when their endogenous glycogen stores are exhausted.
Mol Biochem Parasitol 1987 Jul
PMID:Glycogen metabolism in Schistosoma mansoni worms after their isolation from the host. 362 70

Prepatent and patent adult Hymenolepis diminuta from the intestines of rats, H. diminuta eggs recovered from the faeces of rats harbouring patent infections, and infective cysticercoids from the beetle intermediate host were analysed for free and conjugated ecdysteroids. Adult worms and eggs contained both free ecdysteroids and hydrolysable polar conjugated ecdysteroids, with comparatively large amounts of immunoreactive material also being detected following hydrolysis of the possible apolar conjugated ecdysteroid fraction. Free ecdysteroids were not detected in the cysticercoid sample. The concentration of free ecdysteroids in H. diminuta eggs was higher than that detected in the tissues of the adult worms. Ecdysone and 20-hydroxyecdysone were the major identified compounds of the free ecdysteroid fraction, whereas in the hydrolysed polar conjugated ecdysteroid fraction these two compounds were accompanied by 20,26-dihydroxyecdysone. The free ecdysteroid fraction also contained comparatively large amounts of unidentified immunoreactive material.
Mol Biochem Parasitol 1987 Aug
PMID:Analysis of ecdysteroids in different developmental stages of Hymenolepis diminuta. 367 Mar 43

The molecular model of myohemerythrin, an oxygen-carrying protein from sipunculan worms, has been refined by stereochemically restrained least-squares minimization at 1.7/1.3 A resolution to a conventional R-value of 0.158. The estimated positional standard deviation is better than 0.15 A for most of the 979 protein atoms. The average isotropic displacement parameter, B, for the protein atoms is 23.1 A2. This high average B parameter appears to be due to the overall motion of the molecule, which correlates with the observed anisotropic diffraction. The side-chains of seven residues were modeled in two conformations, i.e. the side-chains were discretely disordered, and B parameters for several lysine and glutamate side-chains indicate that they are poorly localized. Of the residues in myohemerythrin, 66% are helical, with 62% occurring in four long alpha-helices with mean values for the backbone torsion angles of phi = -65 degrees, psi = -42 degrees, and for the hydrogen bonds distances of N ... O, 3.0 A and H ... O, 2.1 A, and angles of N ... O = C, 153 degrees, N-H ... O, 157 degrees, and H ... O = C, 147 degrees. For two-thirds of the alpha-helical residues, the torsional rotation of the C alpha-C beta bond, chi 1, is approximately -60 degrees, and for one-third chi 1 is approximately 180 degrees. Although most turns in myohemerythrin are well-categorized by previous classification, two do not fit in established patterns. Also included in the refined model are three sulfate ions, all partially occupied, and 157 water molecules, 40% of which are modeled fully occupied. Only one water molecule is internal to the protein, the remainder occur on the surface and are observed principally between symmetry-related molecules contributing, along with van der Waals' contacts, most of the interactions between molecules. There are eight intermolecular protein-protein hydrogen bonds, of which only four are between well-located atoms.
J Mol Biol 1987 Sep 20
PMID:Structure of myohemerythrin in the azidomet state at 1.7/1.3 A resolution. 368 96

A cDNA library constructed from RNA isolated from adult Schistosoma mansoni has been screened by differential hybridization to identify clones corresponding to genes highly expressed by female worms. Several such cDNAs encoding the same highly abundant mRNA species were identified. Studies with one of these (pSF10) which contained a 500 base pair insert demonstrated that this gene was not expressed in immature females or eggs and encoded a polypeptide of approximately 35 000 daltons. Quantitation of the levels of RNA showed that 10% of the total RNA of female parasites was homologous to pSF10. A single gene corresponding to pSF10 was identified in Southern blotting experiments using adult worm DNA. The cloning of this gene will facilitate study of the molecular and genetic events controlling female schistosome maturation.
Mol Biochem Parasitol 1986 Jan
PMID:Cloning of a major developmentally regulated gene expressed in mature females of Schistosoma mansoni. 375 7


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