Biology Reference
In-Depth Information
TABLE 12.3
Partial list of Membrane Marker Enzymes.
Membrane
Marker enzyme
Plasma Membrane
5'-Nucleosidase
Alkaline Phosphodiesterase
Na
þ
/K
þ
ATPase
Adenylate Cyclase
Amino Peptidase
Mitochondria Inner
Cytochrome c Oxidase
Succinate-Cytochrome c
Oxidoreductase
Mitochondria Outer
Monoamine Oxidase
Lysosome
Acid Phosphatase
b
-Galactosidase
Peroxisome
Catalase
Urate Oxidase
D-Amino Acid Oxidase
Golgi
Galactosyltransferase
a
-Mannosidase
Endoplasmic Reticulum
Glucose-6-Phosphatase
Choline Phosphotransferase
NADPH-Cytochrome c
Oxidoreductase
(Cytosol)
Lactate Dehydrogenase
SUMMARY
Purifying a membrane is as much an art as it is a science. The first step in purifying
a membrane is breaking open (homogenizing) the cell. Once broken, the many cell membrane
components must be fractionated. Methods discussed include:
Homogenization Methods: Enzymes to break thick cell wall; Shear force (mortar and
pestle); Food blenders; High speed blade-type homogenizers; Osmotic gradients; Sonicators;
Gas ebullition; French Press; and Freeze/thaw.
Fractionation Methods: Centrifugation methods (differential centrifugation and density
gradient centrifugation); Non-centrifugation methods (lectin-affinity chromatography, anti-
body-affinity chromatography, ligand-receptor affinity chromatography, anion exchange
chromatography, magnetic beads, microbeads, two-phase partitioning, silica particles, size
filtration and size exclusion chromatography).
