Cholinesterases enzyme purification

Affinity chromatography is one of the most effective procedures for enzyme purification and yet, with the notable exceptions of Picard (PIO) and of La Du and his co-workers (L2), it has received scant attention for the purification of cholinesterase. Its value in purifying acetylcholinesterase from both fish electric organ and erythrocyte membrane is discussed in an excellent review by Rosenberry (R8). In affinity... 

Augustinsson (A25) studied the cholinesterase activities of the plasmas of many vertebrate species. Subsequent workers have confirmed that the highest activity of the enzyme is found in equine and human plasma or serum. These sources have been used consequently by most workers as starting materials for the purification of cholinesterase. Outdated plasma from national blood banks is valuable for large-scale preparations of the human enzyme. 

K31), who found that benzoylcholinesterase activity varies widely among the sera of various rabbits. Unfortunately, the relevant genetics were not investigated. The presence of butyrylcholine esterase may also be questioned it acts—apparently—as a monomer in rabbit sera, but as a tetramer in human and horse sera. Perhaps the apparent absence of the tetramer and other polymers in some rabbits is the result of the inhibition or complete absence of an aggregating enzyme Does such an enzyme control the interconvertibility of the isoenzymes which are present in other plasma It is relevant that Main (private communication) isolated from rabbit liver cholinesterase two monomer forms of butyrylcholine esterase, one of which spontaneously formed a tetramer after purification. 

D3. Das, P. K., Purification of two unusual serum cholinesterase variants (ChP and Chf) and comparison of their properties with those of normals. Enzyme 18, 279-292 (1974). 

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