# The Role of Glyceraldehyde-3-Phosphate Dehydrogenase in 2-Ketogluconic Acid Industrial Production Strain Pseudomonas plecoglossicida JUIM01

## TL;DR

This study shows that removing a specific gene in a bacteria strain improves the production of a valuable industrial acid.

## Contribution

The novel finding is that deleting the gapA gene enhances 2KGA production in Pseudomonas plecoglossicida JUIM01.

## Key findings

- Deleting gapA increased 2KGA production by 5.7–6.6%.
- The sugar–acid conversion rate and productivity also improved.
- Cell growth was unaffected by the gene deletion.

## Abstract

The full-length gapA gene (1002 bp) was cloned from Pseudomonas plecoglossicida JUIM01, an industrial strain used for 2-ketogluconic acid (2KGA) production. The protein encoded by gapA (designated Gap) was predicted to be a canonical NAD(P)-dependent glyceraldehyde-3-phosphate dehydrogenase that catalyzes the interconversion between glyceraldehyde-3-phosphate and 1,3-bisphosphoglycerate. Bioinformatics analyses and electrophoretic mobility shift assays suggested that gapA is regulated by the transcription factor HexR. Through the knockout and complementation of the gene, along with shake-flask experiments and fermentation in bioreactors, this study demonstrated that the deletion of gapA increased the 2KGA production, sugar–acid conversion rate, molar yield, and productivity of P. plecoglossicida JUIM01 by 5.7–6.6% without affecting cell growth, highlighting the mutant’s significant industrial potential.