Real-time PCR optimization to identify environmental Vibrio spp. strains

Area of Science:

• Environmental microbiology
• Molecular biology

Background:

• Marine environments harbor diverse Vibrio species, including potential human pathogens.
• Accurate identification of Vibrio species is crucial for public health and environmental monitoring.

Purpose of the Study:

• To develop and standardize DNA extraction and real-time PCR assays for identifying Vibrio vulnificus, Vibrio cholerae, and Vibrio alginolyticus.
• To screen a large collection of bacterial strains isolated from marine environments.

Main Methods:

• Standardized DNA extraction using microplates.
• Developed three real-time PCR assays targeting the dnaJ gene for V. vulnificus, V. cholerae, and V. alginolyticus.
• Applied assays to identify 961 Vibrio strains isolated at 22°C and 37°C.

Main Results:

• The real-time PCR assays demonstrated specificity and reproducibility.
• Vibrio alginolyticus was predominant (82.6%) among strains isolated at 37°C.
• At 22°C, only 1.6% of strains were identified as V. alginolyticus, indicating higher species diversity.

Conclusions:

• The standardized DNA extraction and real-time PCR protocol is an effective tool for identifying pathogenic Vibrio species in large environmental collections.
• For strains isolated at lower temperatures (22°C), alternative methods like sequencing may be necessary due to increased species diversity.