Abstract: | Enterococci produced assimilatory ferric reductases which are surface-associated enzymes. This is the first report of the intracellular enzymic reduction of iron by enterococci. A correlation between ferric reductases activity and species affiliation and origin of strains was found. The expression of ferric reductases has not affected by the presence or absence of iron, hemin and hemoglobin in the growth medium. Enterococcal ferric reductases exhibit a very broad specificity. A number of different ferric organic and inorganic compounds, natural and synthetic iron chelators and iron body sources including lactoferrin, transferin, ferritin, haemoglobin, could be reduced. A surface-associated ferric reductases may be one component of a general iron scavenging mechanism which can be used by enterococci growing in a variety of environments. |