How did LUCA make a living? Chemiosmosis in the origin of life
Despite thermodynamic, bioenergetic and phylogenetic failings, the 81-year-old concept of primordial soup remains central to mainstream thinking on the origin of life. But soup is homogeneous in pH and redox potential, and so has no capacity for energy coupling by chemiosmosis. Thermodynamic constra...
Saved in:
Published in | BioEssays Vol. 32; no. 4; pp. 271 - 280 |
---|---|
Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
Weinheim
Wiley-VCH Verlag
01.04.2010
WILEY-VCH Verlag WILEY‐VCH Verlag Wiley Subscription Services, Inc |
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Despite thermodynamic, bioenergetic and phylogenetic failings, the 81-year-old concept of primordial soup remains central to mainstream thinking on the origin of life. But soup is homogeneous in pH and redox potential, and so has no capacity for energy coupling by chemiosmosis. Thermodynamic constraints make chemiosmosis strictly necessary for carbon and energy metabolism in all free-living chemotrophs, and presumably the first free-living cells too. Proton gradients form naturally at alkaline hydrothermal vents and are viewed as central to the origin of life. Here we consider how the earliest cells might have harnessed a geochemically created proton-motive force and then learned to make their own, a transition that was necessary for their escape from the vents. Synthesis of ATP by chemiosmosis today involves generation of an ion gradient by means of vectorial electron transfer from a donor to an acceptor. We argue that the first donor was hydrogen and the first acceptor CO₂. |
---|---|
Bibliography: | http://dx.doi.org/10.1002/bies.200900131 istex:B37F4E70EC6264F64069DD620B63B13950222E81 ark:/67375/WNG-MX778RD6-B ArticleID:BIES200900131 ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0265-9247 1521-1878 |
DOI: | 10.1002/bies.200900131 |