ISSN:
1432-1955
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract A λZAPII cDNA library ofEchinococcus granulosus larvae was expressed inEscherichia coli SURE cells. Screening of the library with a rabbit antiserum raised against total larval antigen yielded several immunoreactive clones. For analysis of the nucleotide sequence, in vivo excision into pBlueskript was carried out and the 3′ end of the cloned insert was sequenced. Three of these clones exhibited identical nucleotide sequences, suggesting expression of identical genes. The complete nucleotide sequence of the largest clone, EG36, with a 3.4-kb insert was determined, presenting an open reading frame of 2.59 kb. The predicted amino acid sequence showed 71.4% identity to theSchistosoma mansoni paramyosin and a significant homology to a 17 amino-acid peptide sequence from antigen B ofTaenia solium. From these data we conclude that EG36 is the paramyosin ofE. granulosus. For protein purification, the coding sequence of the cDNA was amplified by polymerase chain reaction and ligated in frame into the expression vector pGEX-3X. Affinity-chromatography-purified GST fusion protein was used to induce a polyclonal rabbit antiserum. Immunoblot analysis revealed the expression of a 97-kDa protein by theE. coli clone and that of a protein with a similar molecular weight in protoscolices fromE. granulosus andE. multilocularis as well as inE. granulosus cyst fluid. Immunofluorescence studies showed that EG36 was localized throughout the tegument ofE. granulosus andE. multilocularis larvae. Sera from patients suffering from echinococcosis, schistosomiasis, and neurocysticercosis reacted with the purified fusion protein when tested in an enzyme-linked immunosorbent assay.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00932508
