Cloning and sequence analysis of Hemonchus contortus HC58cDNA.
The complete coding sequence of Hemonchus contortus HC58cDNA was generated by rapid amplification of cDNA ends and polymerase chain reaction using primers based on the 5' and 3' ends of the parasite mRNA, accession no. AF305964. The HC58cDNA gene was 851 bp long, with open reading frame of 717 bp, precursors to 239 amino acids coding for approximately 27 kDa protein. Analysis of amino acid sequence revealed conserved residues of cysteine, histidine, asparagine, occluding loop pattern, hemoglobinase motif and glutamine of the oxyanion hole characteristic of cathepsin B like proteases (CBL). Comparison of the predicted amino acid sequences showed the protein shared 33.5-58.7% identity to cathepsin B homologues in the papain clan CA family (family C1). Phylogenetic analysis revealed close evolutionary proximity of the protein sequence to counterpart sequences in the CBL, suggesting that HC58cDNA was a member of the papain family.
Muleke
Charles I
CI
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, Jiangsu, People's Republic of China.
Ruofeng
Yan
Y
Lixin
Xu
X
Xinwen
Bo
B
Xiangrui
Li
L
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002401:Cathepsin B; D003001:Cloning, Molecular; D003546:Cysteine Endopeptidases / Q000737:chemistry / Q000235:genetics*; D018076:DNA, Complementary; D006189:Haemonchus / Q000235:genetics*; D015801:Helminth Proteins / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
D018076:DNA, Complementary; D015801:Helminth Proteins; D011994:Recombinant Proteins; D003546:Cysteine Endopeptidases; D002401:Cathepsin B