Related Experiment Video
Updated: Jun 5, 2025

Author Spotlight: Identifying Compensatory Pathways in Malaria Parasites Containing Hypomorphic Allele of Essential Protein Kinases
Published on: November 22, 2024
The conserved active site aspartate residue is required for the function of the chloroplast atypical kinase ABC1K1
Maud Turquand1, Ana Rita Justo Da Silva1, Thibaut Pralon2
1Plant Physiology Laboratory, Institute of Biology, Université de Neuchâtel, Neuchâtel, Switzerland.
Introduction:
The Arabidopsis abc1k1/pgr6 (Activity of BC1 complex/proton regulation 6) mutant is characterized by photosynthetic and conditional developmental phenotypes triggered by stressful red as well as high light. The Arabidopsis ABC1-like kinases belong to the atypical kinase family and contain conserved ATP-binding and hydrolysis motifs, but their physiological requirement has never been investigated.
Methods:
By mutation to asparagine, we demonstrate that the highly conserved active site aspartate residue within ATP-binding motif VIIb is required for the physiological functions of ABC1K1.
Results:
Complementation of the abc1k1 knock out mutant with ABC1K1 D400N, failed to restore the wildtype phenotype.
Discussion:
These results provide in vivo evidence for a critical role of the active site aspartate residue (D400) of ABC1K1.
Related Concept Videos
Allosteric Proteins-ATCase
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis...
ABC Transporters: Exporter
Protein Kinases and Phosphatases
Protein kinases
Many proteins in the cell are regulated by phosphorylation, the addition of a phosphate group. A family of enzymes called kinases...
Phosphorylation
During phosphorylation, protein kinases transfer the terminal phosphate group of ATP to specific amino acid side chains of substrate proteins. Serine, threonine, and tyrosine are the most commonly...
ATP Synthase: Structure
Protein Transport to the Inner Chloroplast Membrane

