What Is Galacturonokinase (AtGalAK)?

Galacturonokinase, encoded by the AtGalAK gene in Arabidopsis thaliana, is a sugar kinase that catalyzes the transfer of a phosphate group from ATP to D-galacturonic acid, yielding D-galacturonic acid-1-phosphate and ADP. This phosphorylated intermediate is a precursor in the biosynthesis of UDP-D-galacturonic acid, the activated nucleotide sugar required for pectin synthesis in plant cell walls.

AtGalAK belongs to the GHMP kinase superfamily and represents a critical regulatory node in the myo-inositol oxygenation pathway and the salvage/recycling pathway for galacturonic acid in plants. Understanding this enzyme is important for research into plant cell wall composition, biomass quality, and carbohydrate metabolism.

Enzyme Activity, Substrate Specificity & Reaction Conditions

AtGalAK exhibits specificity for D-galacturonic acid as the sugar substrate and requires ATP as the phosphate donor, with divalent metal ions (typically Mg²⁺) as essential cofactors for activity. The enzyme follows the kinetic mechanism characteristic of the GHMP kinase family, involving an ordered sequential binding of substrates.

For in vitro activity assays, standard biochemical buffer systems containing MgCl₂ are commonly employed. Researchers should verify optimal pH, temperature, and cofactor concentrations empirically for their specific experimental system. Coupling assays using ADP detection reagents (e.g., pyruvate kinase/lactate dehydrogenase systems) are frequently used to measure kinase activity.

Storage, Handling & Quality

Recombinant AtGalAK should be stored according to the conditions specified on the product datasheet. As with most recombinant enzymes, storage at −20 °C or −80 °C in an appropriate buffer containing a cryoprotectant such as glycerol is generally recommended to maintain activity over time. Repeated freeze–thaw cycles should be avoided; aliquoting upon receipt is strongly advised.

Handle the enzyme on ice during experimental setup. Aladdin Scientific's Galacturonokinase (AtGalAK), SKU G1432914, is quality-tested for enzymatic activity prior to release. Consult the product-specific Certificate of Analysis (CoA) for confirmed purity, concentration, and activity data.

Applications in Research

AtGalAK is a valuable tool enzyme for researchers studying plant carbohydrate metabolism, cell wall biosynthesis, and nucleotide sugar pathways. Key research applications include:

• Enzyme kinetics studies: Characterizing substrate affinity (Km), maximum velocity (Vmax), and inhibitor profiling.
• Pathway reconstruction: In vitro reconstitution of the UDP-galacturonic acid biosynthesis pathway.
• Structural biology: Crystallography or cryo-EM studies of GHMP kinase family members.
• Metabolic engineering: Engineering plant or microbial systems for modified cell wall or pectin composition.

Its role at the intersection of primary cell wall metabolism and pectin biosynthesis makes it particularly relevant for plant biotechnology and biomass research communities.

Ordering & Product Information

Aladdin Scientific offers Galacturonokinase (AtGalAK) under SKU G1432914. To place an order or request a quotation, contact your regional Aladdin Scientific representative or visit the product page on the Aladdin website.

For bulk quantities, custom formulations, or additional technical support, please reach out to our technical support team. A Certificate of Analysis is available upon request for each production lot. Ensure to review storage and handling requirements on receipt to maintain product integrity.