Protein Engineering of Nicotinamide Riboside Kinase Based on a Combinatorial Semirational Design Strategy for Efficient Biocatalytic Synthesis of Nicotinamide Mononucleotides.
Level 5 - mechanism / opinion, no new human data
Bench research / in vitro protein engineering and biocatalytic process optimization (no human data)
PubMed 39481026 · doi:10.1021/acs.jafc.4c05520
What was done
Nicotinamide riboside kinase was engineered using a docking combination simulation semirational mutagenesis strategy to improve enzymatic phosphorylation for β-nicotinamide mononucleotide (β-NMN) production. Structural stability was evaluated using molecular dynamics simulations and structural analysis. The engineered enzyme was scaled up in a 5 L high-density fermentation tank and paired with an ATP-cycling whole-cell catalytic system utilizing a polyphosphate kinase 2 recombinant strain in batch transformation experiments.
What was found
The engineered variant NRK-TRA achieved a 2.9-fold increase in enzymatic activity compared to the baseline enzyme. High-density fermentation in a 5 L tank reached an enzyme titer of 208.3 U/mL. In batch biotransformation assays using the coupled ATP-regeneration system, β-NMN production reached 15.16 g/L.
Why it matters
The study provides an engineered kinase and ATP-cycling system that lowers cofactor costs and increases yield for the industrial biocatalytic synthesis of β-NMN.
Limits
This is purely an in vitro and bench-scale fermentation study without clinical, biological in vivo, or full industrial scale-up validation. Details on total reaction conversion efficiency, long-term enzyme durability, purification requirements, and downstream economic viability were not reported in the abstract.
Cited by
- supports Nicotinamide mononucleotide (NMN) is harder to synthesize than nicotinamide riboside because it is a larger molecule containing a phosphate group requiring difficult phosphate chemistry.