Candida utilis NAD+ kinase: purification, properties and affinity gel studies

Area of Science:

• Biochemistry
• Enzymology

Background:

• NAD+ kinase (EC 2.7.1.23) is a crucial enzyme in NAD+ metabolism.
• Understanding enzyme kinetics and purification is vital for biochemical research.

Purpose of the Study:

• To purify NAD+ kinase to apparent enzymic homogeneity.
• To characterize the molecular weight and subunit composition of the purified enzyme.
• To propose a method for assessing affinity gel elution patterns.

Main Methods:

• Affinity chromatography using Blue Sepharose CL-6B.
• Polyacrylamide gel electrophoresis (PAGE) for molecular weight determination.
• Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) for subunit analysis.

Main Results:

• NAD+ kinase was purified to apparent enzymic homogeneity.
• The active enzyme species has a molecular weight of approximately 260,000.
• SDS-PAGE revealed a single subunit of approximately 32,000 molecular weight.
• Elution diagrams were proposed for assessing affinity gel desorption.

Conclusions:

• The study successfully purified and characterized NAD+ kinase.
• The findings provide insights into the enzyme's quaternary and subunit structure.
• A novel method for analyzing affinity chromatography elution is presented.