Biomaterial Database

Isolation of cathepsin D from human leucocytes. 1977

I Ishikawa, and G Cimasoni

Acid and neutral protease activities were determined in the granule fractions of polymorpho and mononuclear leucocytes, separated from human blood by means of a discontinuous density gradient centrifugation. The mononuclear leucocytes contained only acid protease while preparations from polymorphonuclear leucocytes showed a predominant activity at neutral pH with a small peak in the acid range. A separation of the acid from the neutral enzyme could be obtained in the granule fraction of polymorphonuclear leucocytes by means of DEAE chomatography. The acid enzyme was then purified from a mixture of leucocytes, more than 400 times, by means of gel chromatography with Sephadex G-200 superfine. The purified acid protease showed an optimum pH of 3.6, had a molecular weight at 42 000 and was characterized by a single protein band (Rf = 0.31) by disc-gel electrophoresis. With all probability this enzyme can be classified as cathepsin D (EC 3.4.4.23).

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D007962	Leukocytes	White blood cells. These include granular leukocytes (BASOPHILS; EOSINOPHILS; and NEUTROPHILS) as well as non-granular leukocytes (LYMPHOCYTES and MONOCYTES).	Blood Cells, White,Blood Corpuscles, White,White Blood Cells,White Blood Corpuscles,Blood Cell, White,Blood Corpuscle, White,Corpuscle, White Blood,Corpuscles, White Blood,Leukocyte,White Blood Cell,White Blood Corpuscle
D009000	Monocytes	Large, phagocytic mononuclear leukocytes produced in the vertebrate BONE MARROW and released into the BLOOD; contain a large, oval or somewhat indented nucleus surrounded by voluminous cytoplasm and numerous organelles.	Monocyte
D009504	Neutrophils	Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.	LE Cells,Leukocytes, Polymorphonuclear,Polymorphonuclear Leukocytes,Polymorphonuclear Neutrophils,Neutrophil Band Cells,Band Cell, Neutrophil,Cell, LE,LE Cell,Leukocyte, Polymorphonuclear,Neutrophil,Neutrophil Band Cell,Neutrophil, Polymorphonuclear,Polymorphonuclear Leukocyte,Polymorphonuclear Neutrophil
D002403	Cathepsins	A group of lysosomal proteinases or endopeptidases found in aqueous extracts of a variety of animal tissues. They function optimally within an acidic pH range. The cathepsins occur as a variety of enzyme subtypes including SERINE PROTEASES; ASPARTIC PROTEINASES; and CYSTEINE PROTEASES.	Cathepsin
D003594	Cytoplasmic Granules	Condensed areas of cellular material that may be bounded by a membrane.	Cytoplasmic Granule,Granule, Cytoplasmic,Granules, Cytoplasmic
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man