Identification and characterization of a cathepsin L-like cysteine protease from Taenia solium metacestode.
Taenia solium metacestode, a larval pork tapeworm, is a causative agent of neurocysticercosis, one of the most common parasitic diseases in the human central nervous system. In this study, we identified a cDNA encoding for a cathepsin L-like cysteine protease from the T. solium metacestode (TsCL-1) and characterized the biochemical properties of the recombinant enzyme. The cloned cDNA of 1216 bp encoded 339 amino acids with an approximate molecular weight of 37.6 kDa which containing a typical signal peptide sequence (17 amino acids), a pro-domain (106 amino acids), and a mature domain (216 amino acids). Sequence alignments of TsCL-1 showed low sequence similarity of 27.3-44.6 to cathepsin L-like cysteine proteases from other helminth parasites, but the similarity was increased to 35.9-55.0 when compared to mature domains. The bacterially expressed recombinant protein (rTsCL-1) did not show enzyme activity; however, the rTsCL-1 expressed in Pichia pastoris showed typical biochemical characteristics of cysteine proteases. It degraded human immunoglobulin G (IgG) and bovine serum albumin (BSA), but not collagen. Western blot analysis of the rTsCL-1 showed antigenicity against the sera from patients with cysticercosis, sparganosis or fascioliasis, but weak or no antigenicity against the sera from patients with paragonimiasis or clonorchiasis.
Li
Ai Hua
AH
Division of Malaria and Parasitic Diseases, National Institute of Health, Korea Centers for Disease Control and Prevention, Seoul 122-701, Republic of Korea.
Moon
Sung-Ung
SU
Park
Yun-Kyu
YK
Na
Byoung-Kuk
BK
Hwang
Myung-Gi
MG
Oh
Chang-Mi
CM
Cho
Shin-Hyeong
SH
Kong
Yoon
Y
Kim
Tong-Soo
TS
Chung
Pyung-Rim
PR
D000595:Amino Acid Sequence; D000818:Animals; D056668:Cathepsin L; D002403:Cathepsins / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D003546:Cysteine Endopeptidases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D018076:DNA, Complementary / Q000737:chemistry; D018509:DNA, Helminth / Q000737:chemistry*; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism; D008967:Molecular Biology; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010802:Phylogeny; D016415:Sequence Alignment; D013045:Species Specificity; D013379:Substrate Specificity; D041201:Taenia solium / Q000201:enzymology*
D018076:DNA, Complementary; D018509:DNA, Helminth; D007074:Immunoglobulin G; D002403:Cathepsins; D003546:Cysteine Endopeptidases; C534281:CTSL protein, human; D056668:Cathepsin L