Aqueous microdroplets promote C-C bond formation and sequences in the reverse tricarboxylic acid cycle.
Nat Ecol Evol
; 7(11): 1892-1902, 2023 Nov.
Article
in En
| MEDLINE
| ID: mdl-37679455
ABSTRACT
The reverse tricarboxylic acid cycle (rTCA) is a central anabolic network that uses carbon dioxide (CO2) and may have provided complex carbon substrates for life before the advent of RNA or enzymes. However, non-enzymatic promotion of the rTCA cycle, in particular carbon fixation, remains challenging, even with primordial metal catalysis. Here, we report that the fixation of CO2 by reductive carboxylation of succinate and α-ketoglutarate was achieved in aqueous microdroplets under ambient conditions without the use of catalysts. Under identical conditions, the aqueous microdroplets also facilitated the sequences in the rTCA cycle, including reduction, hydration, dehydration and retro-aldol cleavage and linked with the glyoxylate cycle. These reactions of the rTCA cycle were compatible with the aqueous microdroplets, as demonstrated with two-reaction and four-reaction sequences. A higher selectivity giving higher product yields was also observed. Our results suggest that the microdroplets provide an energetically favourable microenvironment and facilitate a non-enzymatic version of the rTCA cycle in prebiotic carbon anabolism.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Carbon Dioxide
/
Citric Acid Cycle
Language:
En
Journal:
Nat Ecol Evol
Year:
2023
Document type:
Article