Purification and characterisation of blarinasin, a new tissue kallikrein-like protease from the short-tailed shrew Blarina brevicauda: comparative studies with blarina toxin.
A new tissue kallikrein-like protease, blarinasin, has been purified from the salivary glands of the short-tailed shrew Blarina brevicauda. Blarinasin is a 32-kDa N-glycosylated protease with isoelectric values ranging between 5.3 and 5.7, and an optimum pH of 8.5 for enzyme activity. The cloned blarinasin cDNA coded for a pre-pro-sequence and a mature peptide of 252 amino acids with a catalytic triad typical for serine proteases and 43.7-54.0% identity to other mammalian tissue kallikreins. Blarinasin preferentially hydrolysed Pro-Phe-Arg-4-methylcoumaryl-7-amide (MCA) and N-tert-butyloxycarbonyl-Val-Leu-Lys-MCA, and preferentially converted human high-molecular-weight kininogen (HK) to bradykinin. The activity of blarinasin was prominently inhibited by aprotinin (K(i) =3.4 nM). A similar kallikrein-like protease, the lethal venom blarina toxin, has previously been purified from the salivary glands of the shrew Blarina and shows 67.9% identity to blarinasin. However, blarinasin was not toxic in mice. Blarinasin is a very abundant kallikrein-like protease and represents 70-75% of kallikrein-like enzymes in the salivary gland of B. brevicauda.
Kita
Masaki
M
Research Center for Materials Science, Nagoya University, Furo-cho, Chikusa, Nagoya 464-8602, Japan.
Okumura
Yuushi
Y
Ohdachi
Satoshi D
SD
Oba
Yuichi
Y
Yoshikuni
Michiyasu
M
Nakamura
Yasuo
Y
Kido
Hiroshi
H
Uemura
Daisuke
D
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D006863:Hydrogen-Ion Concentration; D007610:Kallikreins / Q000737:chemistry / Q000302:isolation & purification*; D008969:Molecular Sequence Data; D011480:Protease Inhibitors / Q000494:pharmacology; D016415:Sequence Alignment; D012788:Shrews; D013379:Substrate Specificity; D020840:Tissue Kallikreins / Q000737:chemistry*
D011480:Protease Inhibitors; D007610:Kallikreins; C502041:blarinasin protein, Blarina brevicauda; D020840:Tissue Kallikreins; C487512:blarina toxin, Blarina brevicauda