Related Experiment Video
Updated: Feb 22, 2026

Extremely Rapid and Specific Metabolic Labelling of RNA In Vivo with 4-Thiouracil Ers4tU
Published on: August 22, 2019
Indispensable residue for uridine binding in the uridine-cytidine kinase family
Fumiaki Tomoike1,2, Noriko Nakagawa3, Kenji Fukui4
1Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan.
Abstract:
Uridine-cytidine kinase (UCK), including human UCK2, are a family of enzymes that generally phosphorylate both uridine and cytidine. However, UCK of Thermus thermophilus HB8 (ttCK) phosphorylates only cytidine. This cytidine-restricted activity is thought to depend on Tyr93, although the precise mechanism remains unresolved. Exhaustive mutagenesis of Tyr93 in ttCK revealed that the uridine phosphorylation activity was restored only by replacement of Tyr93 with His or Gln. Replacement of His117 in human UCK2, corresponding to residue Tyr93 in ttCK, by Tyr resulted in a loss of uridine phosphorylation activity. These findings indicated that uridine phosphorylation activity commonly depends on a single residue in the UCK family.
More Related Videos
08:17A High-Throughput Enzyme-Coupled Activity Assay to Probe Small Molecule Interaction with the dNTPase SAMHD1
Published on: April 16, 2021
10:24NMR-Based Activity Assays for Determining Compound Inhibition, IC50 Values, Artifactual Activity, and Whole-Cell Activity of Nucleoside Ribohydrolases
Published on: June 30, 2019
Related Concept Videos
Biosynthesis of Nucleic Acids
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...
Regulation of the Unfolded Protein Response
Transducer Mechanism: Enzyme-Linked Receptors
Major types that are helpful drug targets include: