Investigations on the Action of the Iron-Containing Growth Factors, Sideramines; and Iron-Containing Antibiotics, Sideromycins

SUMMARY: The formation of catalase activity by an Arthrobacter strain jg-9 is dependent upon the addition of exogenous haemin, or the iron-containing growth factor ferrichrome. The iron-containing antibiotic ferrimycin A inhibited the synthesis of catalase in bacterial suspensions supplemented with ferrichrome, but did not measurably alter catalase formation in suspensions supplemented with haemin. This suggests that ferrichrome is necessary for haemin (catalase) synthesis, and that ferrimycin A acts by blocking this step. Cell-free extracts of Rhodopseudomonas spheroides were able to synthesize haemin when incubated with an oxidizable substrate, protoporphyrin IX and iron supplied as ferrichrome.