Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042961 (volvulus)
 4,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study describes the histological localization of two CuZn superoxide dismutases (SOD1 and SOD2) in the parasitic nematode Onchocerca volvulus, and a functional characterization of the 'extracellular' form of this enzyme (SOD2) which provides evidence that it is involved in the defense against environmental superoxide anion radicals. These essential enzymes are detected in larval and adult stages of the parasite, determined at the mRNA and protein levels by in situ hybridization and immunolocalization studies. These proteins are distributed throughout the worm, at various concentrations with particularly high levels produced in the hypodermis. In vitro maintenance of parasites indicated that SOD2 was secreted outside the parasite into the medium. Baculovirus constructs designed to test the ability of the SOD2 hydrophobic N-terminal region to function in processing and secretion confirmed the ability of this polypeptide sequence to direct the secretion of a marker protein, as well as of the mature SOD2 enzyme. Analyses of the native, mature SOD2 enzyme molecular mass, and the primary and quaternary structure, indicate that unlike other extracellular SODs, the SOD2 is active as a non-glycosylated dimer, rather than as a tetrameric glycoprotein. The detection of SOD2 outside of the parasite maintained in vitro, and the confirmation that the SOD2 is a secreted enzyme, indicate that this enzyme plays a role in the interactive biology of parasitic nematodes with their hosts.
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PMID:Localization and functional analysis of the cytosolic and extracellular CuZn superoxide dismutases in the human parasitic nematode Onchocerca volvulus. 927 79

The study describes the immunohistological localization of the extracellular CuZn superoxide dismutase (SOD2) in the parasitic nematode Onchocerca volvulus. Using specific antiserum raised against a 15-amino-acid peptide from the N-terminal region of the mature protein, this enzyme is detected primarily in the intestinal epithelium of the adult worms and to a lesser extent in the muscle cells of the uterine wall. A blocking experiment with the SOD2 peptide reduced the staining significantly, confirming specificity. The localization profile of SOD2 correlates extremely well with the localization of iron deposits in the gut and uterine muscle cells of adult O. volvulus. The detection of SOD2 in the functional intestine of O. volvulus, together with the evidence that it is a secreted protein, indicates that this enzyme in parasitic nematodes is in a position to interact with host molecules. It also demonstrates the accessibility of the parasite enzyme to an inhibitor or blocking antibody.
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PMID:Onchocerca volvulus: immunolocalization of the extracellular CuZn superoxide dismutase using antibodies raised against a 15-mer epitope of this enzyme. 992 37