Abstract
THE indispensability of iron in the form of protohæmin, the so-called 'X' factor, to the growth of H: influenzæ has long been an accepted fact. Recently, the Lwoffs observed that the oxygen consumption of suspensions of this organism containing minimal amounts of hæmin is remarkably increased by the addition of small quantities of this compound. Accordingly, they concluded that the 'X' factor functions by supplying, to the cell, material from which it can synthesize a catalytic respiratory system comprising cytochrome C and possibly cytochrome oxidase, peroxidase and catalase, although no direct evidence was advanced for the latter1. If there is a correlation between the necessity of the hæmin for growth and its ability to promote oxygen consumption, it should be possible to grow the influenza bacillus by replacing the iron complexes with any other system which is capable of inducing oxygen consumption. Since reversible oxidation-reduction systems of suitable potential can function as efficient respiratory catalysts2, we set out to determine the effect of these systems on the growth of H. influenzæ.
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References
Lwoff, A., and Lwoff, M., Ann. Inst. Pasteur, 59, 129 (1937).
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Broh-Kahn, R. H., and Mirsky, I. A., J. Bact., 35, 455 (1938).
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SNYDER, T., BROH-KAHN, R. Substitution of Cysteine for Protohæmin as the 'X' Factor for Growth of H. influenzæ. Nature 142, 153 (1938). https://doi.org/10.1038/142153a0
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DOI: https://doi.org/10.1038/142153a0
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