TY - JOUR AU - Theil, E C AB - I t remaine1:h now -in the next place to discourse o f the mines o f yron. a mettal which wee may well say is both the best and the worst implement used now in the world . . . . (1) PERSPECTIVES The history of civilization shows a long dependence on iron, particularly after the availability of iron for armaments increased (1). The evolution of organ289 0066-4154/87/0701-0289$02.00 THEIL isms also shows a long dependence on iron, even after the availability was diminished by dioxygen in the atmosphere (2). Ferritin maintains iron in an available, soluble form for use, e.g. in oxygen transfer, electron transfer, nitrogen fixation, and DNA synthesis (ribonucleotide reduction). The solubil­ ity of iron probably became a problem ca 2.5 billion years ago when H20 began to be used as a source of hydrogen for photosynthesis (2). Dioxygen, the byproduct of such photosynthesis and probably the worst environmental pollutant of all time, created a dilemma for iron-dependent organisms: either move to environments devoid of dioxygen or accommodate to the low solubil­ ity of Fe(III) produced by dioxygen from Fe(II). [Fe(III) is ca 10-9 X less soluble than Fe(II) (3). At concentrations greater than 10-18 M, TI - Ferritin: Structure, Gene Regulation, and Cellular Function in Animals, Plants, and Microorganisms JF - Annual Review of Biochemistry DO - 10.1146/annurev.bi.56.070187.001445 DA - 1987-07-01 UR - https://www.deepdyve.com/lp/annual-reviews/ferritin-structure-gene-regulation-and-cellular-function-in-animals-f8ax3J0f0P SP - 289 EP - 315 VL - 56 IS - 1 DP - DeepDyve ER -