Rapid methods for determining decarboxylase activity: arginine decarboxylase

Area of Science:

• Biochemistry
• Clinical Microbiology

Background:

• Arginine decarboxylase (EC 4.1.1.19) activity is crucial in microbial metabolism.
• Existing methods for enzyme activity determination can be time-consuming.

Purpose of the Study:

• To develop a rapid biochemical assay for arginine decarboxylase activity.
• To correlate this method with ornithine and lysine decarboxylase assays.

Main Methods:

• Detection of agmatine, the end product of arginine decarboxylation.
• Utilizing a synthetic medium with arginine and a modified diacetyl reagent.
• Employing differential butanol extraction for amine detection.

Main Results:

• The method allows for detection of enzyme activity within 1-4 hours with concentrated inocula or overnight cultures.
• Successfully avoids indirect measurements based on medium alkalinization.
• Provides a rapid and efficient alternative for clinical settings.

Conclusions:

• A fast and reliable biochemical method for arginine decarboxylase activity determination is established.
• This assay is suitable for routine use in clinical microbiology.
• The study details optimal enzyme parameters and related catabolic pathways.