S. Mumby et al., REACTIVE IRON SPECIES IN BIOLOGICAL-FLUIDS ACTIVATE THE IRON-SULFUR CLUSTER OF ACONITASE, Biochimica et biophysica acta (G). General subjects, 1380(1), 1998, pp. 102-108
Low molecular mass iron (LMrFe) can appear in plasma when the transfer
rin becomes fully iron loaded. Such iron poses a risk factor for oxida
tive damage, and for microbial virulence. A previous novel approach to
the detection and measurement of LMrFe in plasma was the use of the i
ron-binding properties of the glycopeptide antitumour antibiotic bleom
ycin and its ability to degrade DNA In the presence of oxygen, bound i
ron, and an iron reducing agent. Since bleomycin is a non-physiologica
l , ligand with iron-binding and redox cycling properties, it has been
suggested that it may not be a valid biological model far detecting a
nd measuring LMrFe. To address these concerns we have developed a biol
ogical approach to the detection and measurement of LMrFe based on the
activation of iron-requiring aconitase., Parallel measurements, in a
variety of clinical conditions in which there was a complete saturatio
n of the plasma transferrin, showed that the bleomycin assay and the a
conitase assay can give similar results for LMrFe. (C) 1998 Elsevier S
cience B.V.