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Title: Iron: Life’s primeval transition metal
Modern life requires many different metal ions, which enable diverse biochemical functions. It is commonly assumed that metal ions’ environmental availabilities controlled the evolution of early life. We argue that evolution can only explore the chemistry that life encounters, and fortuitous chemical interactions between metal ions and biological compounds can only be selected for if they first occur sufficiently frequently. We calculated maximal transition metal ion concentrations in the ancient ocean, determining that the amounts of biologically important transition metal ions were orders of magnitude lower than ferrous iron. Under such conditions, primitive bioligands would predominantly interact with Fe(II). While interactions with other metals in certain environments may have provided evolutionary opportunities, the biochemical capacities of Fe(II), Fe–S clusters, or the plentiful magnesium and calcium could have satisfied all functions needed by early life. Primitive organisms could have used Fe(II) exclusively for their transition metal ion requirements.  more » « less
Award ID(s):
2142509
PAR ID:
10559971
Author(s) / Creator(s):
; ;
Editor(s):
Darensbourg, Marcetta
Publisher / Repository:
Proceedings of the National Academy of Sciences (PNAS)
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
121
Issue:
38
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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