Advancing PLP Biosynthesis: Enhanced Stability and Activity of EcPdxK via LXTE-600 Immobilization

Abstract

Pyridoxal 5ʹ-phosphate (PLP) plays an essential role in a multitude of cellular processes due to its function as a critical coenzyme. This study introduces a significant advancement in PLP biosynthesis by enhancing the stability and activity of Escherichia coli–derived pyridoxal kinase (EcPdxK) through immobilization on an innovative epoxy resin, LXTE-600. Our approach involved the systematic optimization of enzyme loading, coupling duration, and temperature, which resulted in improved immobilization efficiency and a high loading capacity of 80 mg/g. The characterization of immobilized EcPdxK@LXTE-600 was conducted using Fourier transform infrared spectroscopy (FTIR) and confocal laser scanning microscopy (CLSM), confirming successful immobilization. This process notably enhanced the enzyme's performance, increasing its tolerance to pH and temperature fluctuations, thereby improving its thermal stability. The immobilized EcPdxK@LXTE-600 retained over 80% of its initial activity after 4 weeks of storage at 4°C and could be reused up to eight cycles while maintaining more than 70% of its initial activity. These findings not only demonstrate the efficacy of the LXTE-600-based immobilization method but also suggest promising industrial applications for the sustainable production of PLP, potentially revolutionizing approaches in biotechnological and pharmaceutical sectors.