title: Characterization of a cDNA encoding a subtilisin-like serine protease (NC-p65) of Neospora caninum.
abstract: The NC-p65 cDNA is the first protease sequence cloned and described for Neospora caninum. The full length cDNA was isolated by 5'- and 3'-rapid amplification of cDNA ends (RACE). NC-p65 was composed of 865 amino acids with a predicted signal sequence, a proposed pro-domain, and an internal region of conserved repeats. Analysis of the deduced amino acid sequence revealed that this protein had homology to the serine proteases of the subtilisin-like superfamily (subtilases) and had a predicted active site made up of the catalytic residues, Asp 253, His 309. and Ser 484. Antibodies to recombinant NC-p65 recognized multiple bands on Neospora lysate immunoblots, but most intensely stained a 65 kDa band. When N. caninum proteins were purified with affinity resins specific for NC-p65 and analyzed for enzyme activity, a single specific band of reaction was observed on gelatin-saturated zymograms.
authors.affiliation: Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis 95616, USA.
authors.forename: K
authors.initials: K
authors.lastname: Louie
authors.forename: P A
authors.initials: PA
authors.lastname: Conrad
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan / Q000235:genetics*; D001483:Base Sequence; D018076:DNA, Complementary / Q000235:genetics; D008969:Molecular Sequence Data; D018688:Neospora / Q000201:enzymology / Q000235:genetics*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013381:Subtilisins / Q000235:genetics*
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D018076:DNA, Complementary; D013381:Subtilisins