Isoforms of baker's yeast transketolase

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The influence of dyes on the respiration of baker's yeast

Résumé La respiration de la levure de boulangerie en milieu glucose-phosphate est inhibée par la trypaflavine, le bleu de methylène, le violet de cristal. Cette inhibition disparaît du moins partiellement par addition d'acide nucléique, d'acide adénylique et d'A.T.P.     

Chromatographic forms of baker's yeast cytochrome c

Résumé Les auteurs ont étudié les caractéristiques de trois fractions obtenues par l'extraction du citochrome c de la levure. La première est la forme naturelle, tandis qu'on peut considérer les autres comme des formes artificielles résultant du procédé d'extraction.     

Inhibition of thiamine transport in baker's yeast by methylene blue

Summary Methylene blue was found to inhibit thiamine transport competitively (K_i=0.63 M) in baker's yeast. The dye was also effective in abolishing the growth inhibition ofSaccharomyces cerevisiae by pyrithiamine which is known to be taken up by a common transport system for thiamine in yeast cells. A possible mechanism for the inhibition by methylene blue of the thiamine transport system in baker's yeast is discussed.     

The number of coenzyme binding sites in transketolase from baker's yeast

Zusammenfassung Nachweis, dass 2 Mole Thiamindiphosphat pro Mol Apotransketolase gebunden werden.     

The influence of salts on the inhibition of the respiration of baker's yeast by basic dyes

Résumé MgCl₂ et d'autres sels à des concentrations définies protègent la respiration de la levure de boulangerie contre l'action inhibitrice de colorants basiques.     

Presence of a specific uridine 5'-monophosphate pyrophosphorylase in baker's yeast.

Uridine 5'-monophosphate pyrophosphorylase was found to be present in baker's yeast. The enzyme preparation, purified about 30-fold, shows a strict specificity toward uracil and requires Mg++ for its activity.     

Determination of the binding constant of thiamine diphosphate in transketolase from baker's yeast by circular dichroism titration

Zusammenfassung Mit Hilfe des Circulardichroismus wurde die Bindungskonstante von Thiamindiphosphat in der Transketolase der Bäckerhefe bestimmt.     

Observations on vitamin B12-binding factor from hog gastric mucosa

Riassunto Vengono riferiti i risultati dell'esame con elettroforesi continua su carta di una preparazione dalla mucosa gastrica di maiale dotata di potere di legame sulla vitamina B₁₂ e l'isolamento da essa con metodi di estrazione e di precipitazione frazionata del fattore responsabile di tale legame.     

On the alleged non-existence of orbitals

I argue that the claim made by Scerri that in many-electron atoms, orbitals do not exist according to quantum mechanics, is incorrect, for it relies on the view that orbitals are entities. Orbitals are states, not entities, and their use in describing many-electron atoms should be seen as an approximation. The writings by Scerri and others on the issue of realism that are based on the claim therefore lead astray. I furthermore disentangle two issues that Scerri discusses in arguing for his claim: that of electron correlation and that of the Pauli principle. Finally, I point out that more generally there is a misconception in chemistry of what quantum states are.     

The influence of vitamin E on the expenditure of vitamin A from the liver

Zusammenfassung Die Verminderung des Vitamin-A-Depots in Hühnchenleber wurde während einer Karenzzeit von 4 Wochen untersucht, einerseits bei fettfreier Nahrung, anderseits bei einer Nahrung mit 10% Vitamin-A-und E-freiem Dorschlebertran. Nur bei Zusatz von 0.01% all-rac.--Tocopheryl-acetat war nach Ablauf der Karenzzeit stets 89–91% des Vitamin-A-Depots noch vorhanden. Künstliche Antioxydantia waren bei der fettfreien Nahrung ohne Einfluss auf die Verminderung des Vitamin-A-Depots.     

Influence of vitamin A deficiency on thyroxinemia in the rat]

During the 9 post-weaning weeks there is not in the vitamin A-deficient Rats the regular decrease of the thyroxinemia which occurs in the control Rats. So the vitamin A-deficient Rats studied in plateau of weight have a total thyroxinemia greater than that of control Rats (+71%). It is possible to speculate that numerous symptoms of the deficiency are the result of this hyperthyroxinemia.     

Influence of vitamin A on experimental atherosclerosis in rabbits

Résumé La vitamine A a eu un effet hypocholestérimique modéré (7 à 43%) sur des lapins nourris de 0.2% cholestérol. La gravité de l'athérosclérose moyenne fut réduite de 31% dans la crosse aortique, et de 61% dans l'aorte abdominale. L'administration de vitamine A aux lapins nourris de cholésterol a réduit les niveaux de sérum -glucuronidase d'une manière significative, il est donc possible que cette vitamine ait une influence stabilisatrice sur le lysosome.