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IONS AND SALT ACTION. 71
action and enzyme action by the assumption that the enzymes cause an increase
in those ions, which could cause the reaction without the presence of the enzyme.
On the other hand J. Loeb 1
believes that the enzymes can also be electrolytically
dissociated and that their action depends on the amount of ions. Tims pepsin
is a weak base which forms a salt with the hydrochloric acid added and thai this
salt is more strongly dissociated than the base; for this reason the action of pepsin
is increased by acid.
Many enzymotic processes are influenced by the presence of salts
of the alkalies or alkaline earths. According to Bierry, Giaja and Henri
as well as Preti 2
pancreatic juice dialyzed for a long time has no action
upon starch, but becomes active again on adding NaCl or other salts.
According to Wohlgemuth 3
the diastatic power of saliva is increased
ten-fold by the addition of NaCl. The anions are the active part in both
cases (see page 52 on co-enzymes). The strong retarding action which
NaFl exerts upon the enzymotic cleavage of esters is also to be men-
tioned (Loevenhart and Pierce, Amberg and Loevenhart 4
).
Other actions of salts are also ascribed to ion-action. To these
belong the experiments of Dresser 5
according to which mercury salts,
which are relatively strongly dissociated, have a poisonous action upon
organic formations (yeast, frog heart), while potassium-mercury hypo-
sulphite was nearly non-toxic. As the last-mentioned salt contains
very few free Hg ions the posionous action of the first salt is ascribed to
the ions. Paul and Kronig 6
have arrived at similar results by inves-
tigating the poisonous action of mercury salts upon spores. They found
that KoCy4Hg, which hardly contains any Hg ions, is much less poison-
ous than an equivalent solution of HgCy2- The same conditions were
observed by Maillard 7
for copper salts.
This leads us to the question as to the importance of water and the
mineral bodies, which are of just as great moment for the life of the
cells and their metabolism as the organic constituents. In regard to
the water this follows from the fact that the animal body consists of
about two-thirds water. If we also recall that water is of the
greatest importance for the normal physical condition of the tissues,
that the solution of numerous bodies and the dissociation of chemical
compounds, that all flow of juices, all exchange of material, all supply
of food, all growth or destruction and all removal of destructive prod-
1
Bioch. Zeitschr., 19, 534 (1909).
2
Compt. rend. soc. biol., 60, 479 (1906); 62, 432, (1907); Bioch. Zeitschr., 4, 1
(1907); 40, 357 (1912).
3
Bioch. Zeitschr., 9, 1 (1908).
4
Journ. of Biol. Chem., 2, 397 (1907); 4, 149 (1908).
6
Arch. exp. Pathol, u. Pharm., 32, 456 (1893).
6
Zeitschr. f. physik. Chem., 31, 411 (1896).
7
Compt. rend. soc. biol., 50, 1210 (1898).
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