ペプシン

化学的特性Pepsin is a white or pale yellow powder extracted from the gastric mucosa of pigs, sheep or cattle. Soluble in water, the aqueous solution is acidic. Isoelectric point pH=1. Insoluble in ethanol, chloroform, ether. It is non-toxic and has a special smell of meat; it is hygroscopic. The dry enzyme is relatively stable and will not be inactivated when heated to 1000C for 10min. Its aqueous solution is heated to above 700C or above pH6.2 and begins to inactivate, and when pH>8, it is irreversibly inactivated. It is relatively stable in strong acid solution, and the optimum pH is 1.5-2. Its digestibility is strongest when it contains 0.2% to 0.4% hydrochloric acid (pH 1.6 to 1.8), so it is often used in combination with dilute hydrochloric acid.

解説消化酵素の一種．タンパク質，ペプチドのペプチド結合の加水分解を触媒する酵素．基質特異性は芳香族および酸性アミノ酸残基の隣り(C末端側)を加水分解する．ほ乳類，鳥類の胃液中に前駆体ペプシノーゲンとして分泌され，胃酸によって活性化されペプシンとなる．ブタペプシンは分子量3.6×104，301個のアミノ酸で構成される一本鎖のポリペプチドで，1分子のリン酸を含む．酵素活性は pH 1～2で最大であり，pH 7以上で不可逆的に失活する．ペプシノーゲン-ペプシン変換は，活性化の程度によって3種類のペプシン，A(EC 3.4.23.1)，B(EC 3.4.23.2)，およびC(EC 3.4.23.3)が得られる．[CAS 9001-75-6]森北出版「化学辞典（第2版）

用途たん白質及びペプチドの分解酵素。

用途たん白質及びペプチド分解酵素。

天然物の起源ブタ胃液：60～386

使用Pepsin is an enzyme that is secreted in the digestive track of mammals. It works to break down proteins into smaller peptides which can readily be absorbed by the small intestine.

一般的な説明Pepsin powder is prepared from the gastric mucosa of pigs, cattle or sheep.

製造方法Pepsin is a stomach enzyme that serves to digest proteins found in ingested food. Production method of pepsin: using porcine gastric mucosa as raw material, after extraction with phosphate buffer solution, use DEAE-cellulose column chromatography, and after acidification, use Sephadex C-25 and Sephadex G-25 column chromatography again to refine the product.

純化方法Pepsin is re-chromatographed on a column of Amberlite CG-50 using a pH gradient prior to use. Crystallise it from EtOH. [Richmond et al. Biochim Biophys Acta 29 453 1958, Huang & Tang, J Biol Chem 244 1085 1969, 245 2189 1970.]