Structural and biochemical insights into isophthalate dihydrodiol dehydrogenase from Comamonas testosteroni KF1.

IphB KF1 from Comamonas testosteroni KF1 exhibits a ~4-fold higher catalytic efficiency with NADP+ than NAD+ in oxidizing 1,5-DCD.

• Why it matters: Understanding the structural basis of substrate recognition and cofactor specificity in IphB KF1 is crucial for insights into microbial isophthalate degradation and potential pollutant bioremediation.
• What they did: Researchers determined crystal structures of IphB KF1 in apo, NADP+ bound, and ternary forms, revealing conformational changes, key residues, and conserved motifs related to cofactor binding and substrate specificity.
• The result: These findings elucidate the enzyme’s catalytic mechanism and substrate recognition, providing a foundation for engineering enzymes with enhanced activity for environmental pollutant removal.