8Y2H

GK tetramer of AtP5CS1 filament with adjacent hooks, reaction state

Summary for 8Y2H

• Entry DOI: 10.2210/pdb8y2h/pdb
• Related: 8J0F
• EMDB information: 35901 38855
• Descriptor: Delta-1-pyrroline-5-carboxylate synthase A, ADENOSINE-5'-TRIPHOSPHATE (2 entities in total)
• Functional Keywords: l-proline biosynthesis, filamentous enzyme, transferase, plant protein
• Biological source: Arabidopsis thaliana (thale cress)
• Total number of polymer chains: 8
• Total formula weight: 633973.41

Authors

Zhang, T.,Guo, C.J.,Liu, J.L. (deposition date: 2024-01-26, release date: 2024-06-05, Last modification date: 2024-07-10)

Primary citation

Guo, C.J.,Zhang, T.,Leng, Q.,Zhou, X.,Zhong, J.,Liu, J.L.
Dynamic Arabidopsis P5CS filament facilitates substrate channelling.
Nat.Plants, 10:880-889, 2024

PubMed Abstract: In plants, the rapid accumulation of proline is a common response to combat abiotic stress. Delta-1-pyrroline-5-carboxylate synthase (P5CS) is a rate-limiting enzyme in proline synthesis, catalysing the initial two-step conversion from glutamate to proline. 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.

PubMed: 38740943
DOI: 10.1038/s41477-024-01697-w

Experimental method

ELECTRON MICROSCOPY (3.3 Å)