Conjugation in Escherichia coli: A laboratory exercise

Area of Science:

• Microbiology
• Genetics
• Molecular Biology

Background:

• Bacterial conjugation is a fundamental process of horizontal gene transfer.
• Current undergraduate teaching methods for conjugation often rely on complex physiological or antibiotic resistance assays.
• These methods can be challenging for students lacking foundational biological knowledge.

Purpose of the Study:

• To develop a simplified, rapid laboratory exercise for teaching bacterial conjugation.
• To facilitate student understanding of horizontal gene transfer mechanisms.
• To provide a hands-on learning model using Escherichia coli.

Main Methods:

• A novel laboratory exercise was designed for bacterial DNA transfer via conjugation.
• Transconjugants were identified using antibiotic resistance selection on agar plates.
• Confirmation of correct transconjugants was achieved through agarose gel electrophoresis.

Main Results:

• The developed exercise simplifies the identification of transconjugants.
• The technique is rapid and accessible for undergraduate and high school science students.
• Students successfully applied the method to learn about conjugation.

Conclusions:

• The new laboratory exercise effectively teaches bacterial conjugation and horizontal gene transfer.
• This method enhances student comprehension through a practical, accessible approach.
• Post-experiment, students demonstrated an improved ability to conceptualize DNA transfer methods.