Analysis of iron-binding components in the low molecular weight fraction of rat reticulocyte cytosol.
Rat reticulocytes were incubated with rat 125I-Tf-59Fe under conditions inhibiting heme synthesis. Cytosol, prepared from the reticulocytes, was separated and analysed by gel filtration and Amicon Ultrafiltration. An iron-containing low molecular weight fraction derived from the cytosol was further analysed by HPLC size-exclusion chromatography and HPLC reversed phase chromatography. Conditions inhibiting heme synthesis and uncoupling the oxidative phosphorylations lead to a large increase in the Fe-containing low molecular weight fraction in the cytosol. The components in the low molecular weight fraction have an apparent molecular weight of 5500 Dalton as determined with HPLC size-exclusion chromatography. The low molecular weight fraction contained several iron chelating components like glycin, 1/2 cystine and citrate, but no specific iron-binding proteins, nucleotides or pyrophosphate.
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002352:Carrier Proteins / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D002951:Citrates / Q000032:analysis; D019343:Citric Acid; D003600:Cytosol / Q000032:analysis*; D007501:Iron / Q000378:metabolism*; D008297:Male; D008970:Molecular Weight; D009711:Nucleotides / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains; D012156:Reticulocytes / Q000032:analysis*
D000596:Amino Acids; D002352:Carrier Proteins; D002951:Citrates; D009711:Nucleotides; D019343:Citric Acid; D007501:Iron