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An Oscillating Fermentation System from Yeast.

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Metabolic products of cancer cells have an inhibiting action
on catalase. That healthy cells also contain catalase inhibitors
was shown by inhibition experiments, chiefly with cell
extracts from chicken embryos, which are characterized by
accelerated cell growth similar to cancer tissue. Thermostable, dialysable catalase-inhibitors were found in decreasing
concentrations in liver, heart, and brain. I n the cells of these
organs, the inhibitors are distributed in decreasing amounts
in mitochondria, cell nuclei, and cell membranes.
Nothing is known about the chemical character of these
inhibitors. Catalase-inhibitors of known constitution fall
into three groups: diphenols, metabolic products of tryptophane or 5-hydroxytryptophane, and quaternary ammonium
compounds. Tryptamine and serotonin, which are substrates
of amine oxidase, belong to the second group.
Besides the hydrazides, iodine derivatives of noradrenaline
and tyramine are inhibitors for amine oxidase. It must be
assumed that amine oxidase-inhibiting substances also occur
i n cell extracts.
[GDCh-Ortsverband Mainz (Germany),
[VB 902/208 1 €1
January 7th, 19651
German version: Angew. Chem. 77, 549 (1965)
Preparation and Rearrangement of Distyrylmethanol Derivatives and a New Route to
Reductones
G . Hesse, Erlangen (Germany)
The alcohols ( l ~ ) - ( l d ) were prepared from dibenzylideneacetones with NaBH4 [I]. The reduction proceeds the more
slowly, the richer the ally1 system is in electrons. NaBH4
X-C6H4 -CH CH-CHOH-CH
( I ) (a) X = Y
H
(0 x = Y CI
CH-C6H4-Y
Compound ( I c ) yields triose reductone on ozonolysis,
followed by catalytic hydrogenation. The formation of
reductic acids from a,a-dibenzylidenecyclopentanol and
-hexanol was shown in preliminary experiments [2].
[GDCh-Ortsverband Saarbrucken (Germany),
January 22nd, 19651
[VB 909/215 IE]
German version: Angew. Chem. 77. 550 (1965)
An Oscillating Fermentation System from Yeast
B. Hess, Heidelberg (Germany)
Fermentation by Snccharoniyces carlsbergensis (inositol-lack
mutant) begins to oscillate when oxidative phosphorylation
is prevented. By means of gentle high-pressure extraction or
ultrasound treatment, the oscillating system can be obtained
as a homogeneous cell-free extract of high concentration.
Warming or addition of glucose 6-phosphate causes the
system to oscillate with a period of about 0.1 min-1, a
damping factor of 1.1-1.4 and a Q-value of 4-6 at 25 "C.
Analysis of the enzyme distribution pattern indicates that
all known components of fermentation are present, but the
activity of phosphofructokinase is relatively low. The metabolite pattern of the cold extract (+2 "C) shows the proportions
and levels of an almost frozen fermentation with a relatively
high magnesium concentration and a pyridine nucleotide
concentration of 48 % which takes part in the oscillations.
The rest of the metabolite pattern corresponds to the concentrations which are necessary for a feedback control of
phosphofructokinase and of the glyceraldehyde-3-phosphate
dehydrogenase/phosphoglycerate kinase system. Addition of
substrates and metabolic intermediates can influence the
+ X-C6H4-CHOH -(CH CHkC6H4-Y
(2) ( b ) . X - Y = OCH3
( d ) : X - H, Y = OCH3
does not attack compounds where X = Y = N(CH&, while
o n reduction with LiAIH4 the hydroxy group is eliminated
and 1 ,5-bis-(p-dimethylaminopheny1)-1,3-pentadiene is formed. Acids or activated aluminum oxide cause an aflylic
rearrangement of the alcohols ( I ) to the alcohols (2).
The reaction is of first order with regard to the alcohol
concentration. The rate constants are proportional to the
Hf ion concentration. The methyl ethers of (2) are formed
in methanol. The rearrangement proceeds 1/10 as fast
in dioxane or methanol containing 20
water as in the
anhydrous solvents. Its rate increases again at higher water
content. Compound ( I c ) rearranges more slowly, (Ib)
and ( I d ) rearrange more rapidly than ( l o ) . This corresponds to the basicity of the hydroxy group in these compounds. The reaction probably takes the following course:
partly sinusoidal wave forms, in part with a shift in phase.
Additions of pure fermentation enzymes lead to shifts of the
stationary equilibria of the components involved in the
oscillation. Additions of phosphoglycerate kinase, phosphoglycerate mutase, and enolase sufficient to cause a doubling of
the endogenous enzyme concentration lead to a raise in the
frequency of the oscillations and t o their stabilization. The
activity of these enzymes decreases in the order given. They
cause the average redox state of the pyridine nucleotides to
be shifted toward the oxidized side. Conversely, the addition
of highly purified phosphofructokinase brings about an
increase in frequency and a shift of the average redox state
of the pyridine nucleotide system to the reduced side. These
findings demonstrate the cooperative activity of the glycolytic enzymes during oscillation. It may be assumed that
oscillation is a phenomenon which can be induced in many
varieties of cells and which is of importance for periodic
biological processes.
[Biochemical Colloquium, GieBen (Germany),
January 29th, 19651
[VB 91 1/222 IE]
German version: Angew. Chem. 77, 550 (1965)
New Aspects of the Koch CarboxylicAcid Synthesis
The (colored) carbonium ions can be rendered visible
during the rearrangement by a special procedure: If t h e
rearrangement is carried out in absolute benzene in the
presence of acidic anhydrous silica gel, the reactants of the
final step - water and R'" - are adsorbed at separate points
for a short time before they react with each other. Distyrylmethanol and its derivatives absorb oxygen after a long induction period, whichcan be abolished bythe addition ofdibenzoyl
peroxide. The stability of the preparations increases in the
order ( I b ) < (Id) < ( l a ) < ( I c ) .
The addition of CO and CH3OH to cyclic mono-olefins in
the presence of HIBF3.OCH31 as catalyst 131 does not lead,
in the case of cyclo-octene, cyclononene, and cyclodecene, to
the expected methyl esters of s e c o n d a r y cycloalkanecarboxylic acids. Instead, the methyl esters of t e r t i a r y
[ I ] Experiments
internat. Edit. 3, 148 (1964).
In
cooperation with P . Thieme.
Angew. Chem. iniernrri. Edit.
/
Vol. 4 (1965) [ No. 6
K. E. Moller, Miilheim/Ruhr (Germany)
121 Experiments in cooperation with E . Bnyer.
131 K . E. Moller, Angew. Chem. 75, 1122 (1963); Angew. Chem.
535
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