Dynamic Arabidopsis P5CS filament facilitates substrate channelling.
Nat Plants
; 10(6): 880-889, 2024 Jun.
Article
in En
| MEDLINE
| ID: mdl-38740943
ABSTRACT
In plants, the rapid accumulation of proline is a common response to combat abiotic stress1-7. Delta-1-pyrroline-5-carboxylate synthase (P5CS) is a rate-limiting enzyme in proline synthesis, catalysing the initial two-step conversion from glutamate to proline8. Here we determine the first structure of plant P5CS. Our results show that Arabidopsis thaliana P5CS1 (AtP5CS1) and P5CS2 (AtP5CS2) can form enzymatic filaments in a substrate-sensitive manner. The destruction of AtP5CS filaments by mutagenesis leads to a significant reduction in enzymatic activity. Furthermore, separate activity tests on two domains reveal that filament-based substrate channelling is essential for maintaining the high catalytic efficiency of AtP5CS. Our study demonstrates the unique mechanism for the efficient catalysis of AtP5CS, shedding light on the intricate mechanisms underlying plant proline metabolism and stress response.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Arabidopsis
/
Arabidopsis Proteins
Language:
En
Journal:
Nat Plants
Year:
2024
Document type:
Article
Affiliation country:
China