On-line synthesis utilizing immobilized enzyme reactors based upon immobilized dopamine beta-hydroxylase

Area of Science:

• Biochemistry and Enzymology
• Analytical Chemistry
• Drug Discovery

Background:

• Dopamine beta-hydroxylase (DBH) is crucial in neurotransmitter synthesis.
• Characterizing cytosolic and membrane-bound DBH forms presents challenges.
• Immobilized enzyme reactors (IMERs) offer a platform for enzyme analysis.

Purpose of the Study:

• To develop and characterize novel immobilized enzyme reactors (IMERs) for dopamine beta-hydroxylase (DBH).
• To investigate the on-line hydroxylation activity of DBH immobilized on different stationary phases.
• To establish a coupled chromatographic system for characterizing DBH enzyme-substrate and enzyme-inhibitor interactions.

Main Methods:

• Immobilization of DBH onto immobilized artificial membrane (IAM) and glutaraldehyde-P (Glut-P) stationary phases.
• Development of coupled chromatography system with on-line extraction using a phenylboronic acid column.
• Investigation of enzyme activity, reproducibility, and effects of operational parameters (flow-rate, contact time, pH, temperature).

Main Results:

• Successfully developed enzymatically active and reproducible DBH-IMERs using IAM and Glut-P phases.
• Demonstrated the ability of DBH-IAM-IMER and DBH-Glut-P-IMER to characterize membrane-bound and cytosolic DBH forms, respectively.
• Validated the on-line system for investigating enzyme-substrate and enzyme-inhibitor interactions.

Conclusions:

• The developed DBH-IMERs provide a robust platform for studying DBH.
• The coupled chromatographic system enables efficient on-line characterization of DBH forms and interactions.
• These IMERs are valuable tools for the discovery and characterization of new drug candidates targeting DBH.