Immobilization of the Aspartate Ammonia-Lyase from Pseudomonas fluorescens R124 on Magnetic Nanoparticles: Characterization and Kinetics.

ABSTRACT: Aspartate ammonia-lyases (AALs) catalyze the non-oxidative elimination of ammonia from l-aspartate to give fumarate and ammonia. In this work the AAL coding gene from Pseudomonas fluorescens R124 was identified, isolated, and cloned into the pET-15b expression vector and expressed in E. coli. The purified enzyme (PfAAL) showed optimal activity at pH 8.8, Michaelis-Menten kinetics in the ammonia elimination from l-aspartate, and no strong dependence on divalent metal ions for its activity. The purified PfAAL was covalently immobilized on epoxy-functionalized magnetic nanoparticles (MNP), and effective kinetics of the immobilized PfAAL-MNP was compared to the native solution form. Glycerol addition significantly enhanced the storability of PfAAL-MNP. Inhibiting effect of the growing viscosit

SUBMITTER: Csuka P 

PROVIDER: S-EPMC9307013 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature