Characterization of Clostridium tyrobutyricum Strains Using Three Different Typing Techniques

Area of Science:

• Food microbiology
• Bacteriology
• Dairy science

Background:

• Clostridium tyrobutyricum is a primary cause of severe cheese spoilage.
• Bacterial metabolism during cheese ripening leads to defects and economic losses.
• Strain-level variation in spoilage potential necessitates better differentiation methods.

Purpose of the Study:

• To compare the efficacy of three typing techniques for differentiating Clostridium tyrobutyricum strains.
• To assess the intra-species diversity of C. tyrobutyricum relevant to the dairy industry.

Main Methods:

• Repetitive element palindromic PCR (rep-PCR) with agarose gel electrophoresis.
• Hexaplex-PCR followed by automated capillary electrophoresis.
• Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) typing.

Main Results:

• MALDI-TOF MS showed moderate reproducibility and low discriminatory power.
• Both PCR-based methods (rep-PCR and hexaplex-PCR) were highly reproducible and discriminative.
• Hexaplex-PCR exhibited slightly higher discriminatory power than rep-PCR.

Conclusions:

• A high degree of intra-species diversity was observed in the tested C. tyrobutyricum strains.
• PCR-based methods, particularly hexaplex-PCR, are effective for differentiating C. tyrobutyricum strains.
• Further strain-level investigations are warranted for practical dairy applications.