Biomaterial Database

Differential release of membrane-bound alkaline phosphatase isoenzymes from tumor cells by bromelain. 1980

R H Kottel, and W C Hanford

A rapid enzymatic method is presented which results in the selective release of cell-surface alkaline phosphatase isoenzymes. Treatment of suspensions of human tumor cell lines with the proteolytic enzyme bromelain released certain alkaline phosphatase isoenzymes into low-molecular-weight, catalytically active forms. Cells which expressed term placental or intestinal isoenzymes were equally susceptible to this treatment. A cell line which expressed early placental isoenzyme, however, was unaffected by bromelain as indicated by complete recovery of activity in the treated membrane fraction. Successful solubilization of immunologically reactive enzyme allows quantitation of levels of cell-surface enzyme in response to modulators of gene expression. Moreover, the observed selective solubilization of isoenzymes by bromelain may be of general use in analyses of the physical association between other biologically important surface proteins and the lipid components of the cell membrane.

UI	MeSH Term	Description	Entries
D007122	Immunoelectrophoresis	A technique that combines protein electrophoresis and double immunodiffusion. In this procedure proteins are first separated by gel electrophoresis (usually agarose), then made visible by immunodiffusion of specific antibodies. A distinct elliptical precipitin arc results for each protein detectable by the antisera.
D007527	Isoenzymes	Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.	Alloenzyme,Allozyme,Isoenzyme,Isozyme,Isozymes,Alloenzymes,Allozymes
D001963	Bromelains	Protein-digesting and milk-clotting enzymes found in PINEAPPLE fruit juice and stem tissue. Enzymes from the two sources are distinguished as fruit bromelain and stem bromelain. This enzyme was formerly listed as EC 3.4.22.4.	Bromelins,Ananase,Bromelain,Bromelain-POS,Bromelin,Dayto Anase,Debrase,Dontisanin,Extranase,Mucozym,Proteozym,Traumanase,Bromelain POS,BromelainPOS
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
D006367	HeLa Cells	The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for, among other things, VIRUS CULTIVATION and PRECLINICAL DRUG EVALUATION assays.	Cell, HeLa,Cells, HeLa,HeLa Cell
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000469	Alkaline Phosphatase	An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC 3.1.3.1.
D012995	Solubility	The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Solubilities