Proteomic analysis was employed to elucidate the regulatory role of TtdR, a LysR-type transcriptional regulator located upstream of the glyoxylate carboligase gene (gcl) in Pseudomonas umsongensis GO16. While the wildtype strain can utilize ethylene glycol (EG) as a sole carbon and energy source, the ΔttdR mutant is unable to grow on EG, confirming TtdR as an activator of EG metabolism. Comparative proteomics between the wildtype and ΔttdR strains grown on different carbon sources revealed broad metabolic reprogramming beyond EG utilization. Notably, deletion of ttdR altered the abundance of proteins involved in amino acid metabolism, fatty acid metabolism, and polyhydroxyalkanoate (PHA) metabolism.