Characterization of a novel otubain-like cysteine protease of Cryptosporidium parvum.
Otubains are a recently discovered family of cysteine proteases that participate in the ubiquitin pathway. Here, we partially characterized the biochemical properties of a cysteine protease of Cryptosporidium parvum, which is closely related to otubains. The gene encoding otubain-like cysteine protease of C. parvum (CpOTU) contained the aspartate, cysteine and histidine residues that form the catalytic triad of otubains. The modified ubiquitin-associated domain and LxxL motif were identified in CpOTU. The recombinant CpOTU showed the isopeptidase activity at neutral pH values and its activity was effectively inhibited by ubiquitin aldehyde, N-ethylmaleimide and iodoacetic acid. Interestingly, CpOTU had an unusual C-terminal extension of 217 amino acids compared to mammalian otubains, and the C-terminal extension is essential for the activity of the enzyme. Expression of CpOTU peaked in the oocyst stage of the parasite, which suggested its potential physiological role for the oocyst stage.
Department of Parasitology and Tropical Medicine, Gyeongsang National University School of Medicine, Jinju 660-751, Republic of Korea; Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751, Republic of Korea.
Hye-Lim
HL
Ju
Department of Parasitology and Tropical Medicine, Gyeongsang National University School of Medicine, Jinju 660-751, Republic of Korea; Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751, Republic of Korea.
Jung-Mi
JM
Kang
Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751, Republic of Korea; Department of Biochemistry, Gyeongsang National University School of Medicine, Jinju 660-751, Republic of Korea.
Hae Sook
HS
Noh
Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751, Republic of Korea; Department of Biochemistry, Gyeongsang National University School of Medicine, Jinju 660-751, Republic of Korea.
Deok Ryong
DR
Kim
Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu 700-422, Republic of Korea.
Yeonchul
Y
Hong
Department of Parasitology and Tropical Medicine, Gyeongsang National University School of Medicine, Jinju 660-751, Republic of Korea; Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751, Republic of Korea.
Woon-Mok
WM
Sohn
Department of Parasitology and Tropical Medicine, Gyeongsang National University School of Medicine, Jinju 660-751, Republic of Korea; Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju 660-751, Republic of Korea. Electronic address: bkna@gnu.ac.kr.
Byoung-Kuk
BK
Na
D000595:Amino Acid Sequence; D016785:Cryptosporidium parvum / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D057056:Cysteine Proteases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*
D015800:Protozoan Proteins; D057056:Cysteine Proteases
Cryptosporidium parvum; Cysteine protease; Oocyst; Otubain; Ubiquitin pathway