Racemization in reverse: evidence that D-amino acid toxicity on Earth is controlled by bacteria with racemases.
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ABSTRACT:
SUBMITTER: Zhang G
PROVIDER: S-EPMC3960212 | biostudies-literature | 2014
REPOSITORIES: biostudies-literature
Publications
Racemization in reverse: evidence that D-amino acid toxicity on Earth is controlled by bacteria with racemases.
PloS one 20140319 3
D-amino acids are toxic for life on Earth. Yet, they form constantly due to geochemical racemization and bacterial growth (the cell walls of which contain D-amino acids), raising the fundamental question of how they ultimately are recycled. This study provides evidence that bacteria use D-amino acids as a source of nitrogen by running enzymatic racemization in reverse. Consequently, when soils are inundated with racemic amino acids, resident bacteria consume D- as well as L-enantiomers, either s ...[more]
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