Reference no: EM133124444

Practical: Bacteriology

Gram Stain
Refer to Practical 2, Part 5 for method.

Catalase Production
1. Place a glass slide, your cultured plate and your tootpick container within the zone of sterility.
2. Select a colony from a previously cultured plate using a toothpick. Take care to avoid agar. Smear this onto the surface of a glass slide
3. Place a drop of catalase reagent (hydrogen peroxide) onto the deposited bacteria on the glass slide.
4. Observe the bacteria for the production of bubbles

Note: If the organism is catalase positive, bubbles will develop around the inoculum almost immediately.

Oxidase Production
1. Place a filter paper onto the surface of a glass slide.
2. Add 2 to 3 drops of the oxidase reagent to the filter paper
3. Place the previously cultured agar plate upside down on the bench so that the lid is on the bench.
4. Hold the plate within the zone of sterility leaving the lid on the bench.
5. Using a sterile toothpick pick a single colony of bacteria from a previously cultured plate. Do not use a metal loop.
6. Replace the agar plate lid
7. Smear the bacterial colony onto the filter paper on the surface of a glass slide

Motility Test
Refer to Practical 2, Part 4 for methods. Use the broth cultures provided to complete this test. Bacteria grown on solid media often demonstrate reduced motility.

Acid-Fast Stain (Ziehl-Neelsen)
Observe the slide or laminate of Mycobacterium provided as a demonstration and and illustrate, label and describe your observations.

Spore Stain
Endospores may be observed during the interpretation of a Gram stain, however a special spore stain will demonstrate bacterial spores much more clearly. Cells will stain red while the spores will stain green.
Observe the spore stain preparation or laminate provided as a demonstration and illustrate, label and describe your observations.

Complete Tasks from the Previous Bacteriology Practical
- Examine the plates exposed to the airborne and external body surfaces bacteria. Count the number of colonies formed by the different microorganisms. Describe the bacterial colonies, as outlined in Appendix 1 Macroscopic Examination of Bacteria. Consider What effects do the different hand washing treatments have on the microbial flora?
- Examine the plate inoculated with the nasal swab collection and external body surface swab. Describe the bacterial colonies, as outlined in Appendix 1 Macroscopic Examination of Bacteria. Does your plate indicate the person sampled is carrying a pathogen?
- Examine the plates prepared for the water quality assessment. Count the number of colonies for each dilution. Note: colony morphology is not required for pour plates. How much bacteria was in the original water sample? - include this section only in Practical 3 results

Attachment:- Practical Microscopy and Aseptic Technique.rar