Micro practical 1
BHS002-1 Microbiology Practical
Manipulation of bacteria – Part 1
Week 45
Since the early days of microbiology in the 19th century, culture on agar plates has been a central technique for the study of bacteria. This practical is designed to introduce students to the basic techniques required to manipulate bacteria. Students will gain experience with the streak plate procedure, used to isolate pure colonies of bacteria, and viable plate count methods. The latter involves serial dilution and spread plating of bacteria on agar plates.
Materials required per pair
•
One 10 ml liquid culture of Escherichia coli BL21 (see prior preparation)
•
A sample of Yakult (approximately 5 ml)
•
Marker pens to label plates & bottles
•
Sterile plastic loops for streaking bacteria (up to 20 per pair)
•
Sterile plastic spreaders for spreading bacteria (4 per pair)
•
Sterile universals/bijoux bottles (8 per pair) for serial dilutions
•
10 ml sterile phosphate buffered saline (PBS) per pair
•
P1000 & P100 or P200 pipettes & sterile racked tips
•
6x MacConkey Agar plates per pair (Oxoid CM0007)
•
2x Nutrient Agar (or equivalent) plates per student pair
•
4x MRS agar plates per student pair (De Man, Rogosa, Sharpe; Oxoid CM0361)
•
Sharps bins for loop/spreader disposal
Prior preparation
Approximately 18 hours prior to the practical, for each student group, 10 ml of sterile broth was inoculated with E. coli from an agar plate. Such cultures were incubated at 37°C on a shaking incubator.
Student activity 1 – Streaking bacteria on MacConkey agar
Using a sterile loop, each student should streak an inoculum of the putative E. coli from the prepared culture onto MacConkey agar plates to determine whether the supplied culture contains bacteria with the expected phenotype.
There are a number of patterns that can be used for a streak plate. In order to gain experience of each, each student should streak a sample of E. coli onto a separate MacConkey agar plate using each of
Manipulation of bacteria – Part 1
Week 45
Since the early days of microbiology in the 19th century, culture on agar plates has been a central technique for the study of bacteria. This practical is designed to introduce students to the basic techniques required to manipulate bacteria. Students will gain experience with the streak plate procedure, used to isolate pure colonies of bacteria, and viable plate count methods. The latter involves serial dilution and spread plating of bacteria on agar plates.
Materials required per pair
•
One 10 ml liquid culture of Escherichia coli BL21 (see prior preparation)
•
A sample of Yakult (approximately 5 ml)
•
Marker pens to label plates & bottles
•
Sterile plastic loops for streaking bacteria (up to 20 per pair)
•
Sterile plastic spreaders for spreading bacteria (4 per pair)
•
Sterile universals/bijoux bottles (8 per pair) for serial dilutions
•
10 ml sterile phosphate buffered saline (PBS) per pair
•
P1000 & P100 or P200 pipettes & sterile racked tips
•
6x MacConkey Agar plates per pair (Oxoid CM0007)
•
2x Nutrient Agar (or equivalent) plates per student pair
•
4x MRS agar plates per student pair (De Man, Rogosa, Sharpe; Oxoid CM0361)
•
Sharps bins for loop/spreader disposal
Prior preparation
Approximately 18 hours prior to the practical, for each student group, 10 ml of sterile broth was inoculated with E. coli from an agar plate. Such cultures were incubated at 37°C on a shaking incubator.
Student activity 1 – Streaking bacteria on MacConkey agar
Using a sterile loop, each student should streak an inoculum of the putative E. coli from the prepared culture onto MacConkey agar plates to determine whether the supplied culture contains bacteria with the expected phenotype.
There are a number of patterns that can be used for a streak plate. In order to gain experience of each, each student should streak a sample of E. coli onto a separate MacConkey agar plate using each of