Nisshin Flour Milling Co., Ltd.

Tatsuya Ohwaki

Hiroshi Sakai

Yoshiyuki Tahara

Hitoshi Inoue

Shigeo Kawase

Hiroyuki Yamazaki

Masako Yamada

Prophylactic and therapeutic agent for hepatic diseases

A human endothelin converting enzyme (ECE) has been isolated from blood and placenta. The enzyme has the activity of converting big endothelin-1, -2, or -3 to endothelin-1, -2, or -3 respectively. The enzyme has a mass of about 5.4.times.10.sup.5 by gel filtration, a pH optimum of 6.5 to 7.5, and a hydrated density of less than 1.210. The enzyme is inhibited by EDTA, phosphoramidon, thiorphan, chymostatin and phenylmethylsulfonylfluoride (PMSF). The enzyme is precipitated by 0.65% dextran sulfate or 0.2M manganese chloride. The enzyme can be inactivated by oxidation by copper ion.

Human endothelin converting enzyme obtained from blood or placenta

A method for converting big endothelin-1 to endothelin-1 by contacting big endothelin-1 with a commercially available preparation of apolipoprotein B is presented. The apolipoprotein B itself has the converting enzyme activity.

Method of converting big endothelin-1 to endothelin-1 with human

Human endothelin converting enzyme (ECE) has been isolated from blood or placenta by a series of centrifugation steps at different densities. A first ECE-I is isolated by a low speed centrifugation to produce enzyme with a hydrated density of about 0.94 g/ml. A second high speed centrifugation produces an ECE-II with a hydrated density between about 0.94 to about 1.006 g/ml. After adjusting the density of the solution, a high speed centrifugation isolates an ECE-III with a hydrated density between about 1.006 to about 1.063. A final adjustment to the density of the solution and high speed centrifugation obtains an ECE-IV with a hydrated density of between about 1.063 to about 1.210 g/ml.

Human endothelin converting enzyme isolated from blood or placenta by

Growing community of inventors

Ohimachi, Japan

Tatsuya Ohwaki