The effect of the iron concentration in the medium on the concentration of toxin and coproporphyrin in the culture filtrate of a strain of Corynebacterium diphtheriae has been found to differ quantitatively from that previously reported in the case of the P.W. 8 strain. Only 50-60% of the iron present in the medium, at all concentrations tested, was recoverable from the organisms. Of the total iron present in the medium, only 9% was found to be present in the organisms as a haem complex capable of measurement as its pyridine haemochromogen. On the basis of their iron contents protohaemin and iron coproporphyrin III are less active than ferrous sulphate in their effect on toxin yield. These findings do not support the hypothesis that diphtheria toxin is the protein moiety of the cytochrome b of the cell.
ClarkeW.A.,
ClarkeG.D.1953; The mechanism of the effect of iron and cobalt on the production of toxin by Corynebacterium diphtheriae.
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PappenheimerA.M.JunHendeeE.D.1947; Diphtheria toxin. IV. The iron enzymes of Corynebacterium diphtheriae and their possible relationship to diphtheria toxin. J. biol. Chem. 171:701
PappenheimerA.M.JunHendeeE.D.1949; Diphtheria toxin. V. A comparison between the diphtherial succinoxidase system and that of beef heart muscle. J. biol. Chem 180:597
RawlinsonW.A.,
HaleJ.H.1949; Prosthetic groups of the cytochromes present in Corynebacterium diphtheriae with especial reference to cytochrome a.
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WadsworthA.,
CroweM.O’L.,
SmithL.A.1935; The spectroscopic investigation of bacterial toxins: the absorption spectra of the products of Corynebacterium diphtheriae.
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