O-demethylation of dextromethorphan using microbial cultures

Area of Science:

• Microbiology
• Pharmacology
• Drug Metabolism

Background:

• Dextromethorphan (DXM) metabolism in humans primarily involves CYP 2D6.
• Investigating microbial systems offers potential for alternative drug metabolism studies.
• Understanding microbial biotransformation can provide insights into drug metabolism pathways.

Purpose of the Study:

• To screen various microbes for their ability to metabolize DXM similarly to humans.
• To identify microbial models that can mimic human drug metabolism.
• To explore the potential of microbial systems for producing active drug metabolites.

Main Methods:

• Screening of eight microbial strains for DXM metabolism.
• Characterization of DXM metabolites using High-Performance Liquid Chromatography (HPLC) and Liquid Chromatography-Mass Spectrometry (LC/MS).
• Comparative analysis of microbial DXM metabolism with human metabolic pathways.

Main Results:

• Saccharomyces cerevisiae (NCIM 3090) was identified as a key microbe capable of metabolizing DXM.
• The primary metabolite produced by Saccharomyces cerevisiae was dextrorphan, a known active human metabolite of DXM.
• Microbial metabolism of DXM by Saccharomyces cerevisiae showed similarities to mammalian metabolism.

Conclusions:

• Saccharomyces cerevisiae serves as a suitable in vitro model for mimicking CYP 2D6-mediated DXM metabolism.
• This yeast can be utilized to produce dextrorphan for pharmacological and toxicological research.
• Microbial biotransformation presents a viable alternative system for studying human drug metabolism.