Sensitive radiometric assay for chloramphenicol acetyltransferase using automated HPLC

Area of Science:

• Molecular Biology
• Biochemistry
• Genetics

Background:

• Chloramphenicol acetyltransferase (CAT) is a crucial reporter gene in eukaryotic gene expression studies.
• Existing methods for measuring CAT activity have limitations in sensitivity and efficiency.

Purpose of the Study:

• To introduce a novel, highly efficient technique for quantifying CAT activity.
• To overcome the drawbacks of current CAT assay procedures.

Main Methods:

• Direct reverse-phase High-Performance Liquid Chromatography (HPLC) analysis.
• Utilizing butyryl coenzyme A as a substrate instead of acetyl coenzyme A.
• Implementing automated sample loading and continuous on-line radioactivity detection.

Main Results:

• Elimination of the need for organic extraction.
• Improved chromatographic resolution of radioactive substrates and products.
• Achieved high sensitivity, linearity, precision, and rapid, quantitative results, even for low CAT expression levels.

Conclusions:

• The new CAT assay technique offers significant advantages in sensitivity, speed, and quantitative accuracy.
• This method enhances the study of eukaryotic gene expression by providing more reliable CAT activity measurements.
• The assay is suitable for detecting low levels of cellular CAT expression, broadening its applicability.