2ee3 lab #1 prelab

Bio 2EE3 Lab 1 pre-lab talk

Id tif i Mi b bIdentifying Microbes by Microscopy and PhysiologyMicroscopy and Physiology

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Laboratory SafetyYou must have Biosafety Level 1 Training before working in the laboratory:

register in and complete HTH SCI 1BS0

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Lab coats: Coats must be worn to protect you and your clothing from stains andcorrosive reagents.

Bi h d T t ll i d th h th d d b f lBiohazards: Treat all organisms used as though they are dangerous, and be carefulto avoid any direct contact with them. Do not drink/eat in the laboratory and ASKyour TAs in case you should have any questions. Plates not used any more shouldbe disposed of in the Biohazard waste cartons in the lab.

Spills/Sterilization: There are bottles of a disinfecting solution (5% Dettol) at eachbench for wiping your work areas before the beginning and after the end of work. If aculture is spilled, disinfect the area with 5% Dettol. Wash your hands with thebacteriocidal soap provided before leaving the laboratorybacteriocidal soap provided before leaving the laboratory.

Glass waste: Dispose of slides or damaged glassware that has come in contact withmicroorganisms in the Biohazard sharps containers. Dispose other glass waste inthe Glass waste cartons

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the Glass waste cartons.

Relative sizes of different cells.Bio 2EE3 Lab 1 pre-lab talk

Slonczewski and Foster: Figure 2-43

Common shapes of bacteria.Bio 2EE3 Lab 1 pre-lab talk


Microscopy and X-ray crystallography, f l ti


range of resolution.

Slonczewski and Foster: Figure 2-7 5

Anatomy of a compound microscope.Bio 2EE3 Lab 1 pre-lab talk


Use of immersion oil in microscopy.Bio 2EE3 Lab 1 pre-lab talk



Lab 1 part 1Lab 1 part 1

Work in groups of 4Work in groups of 4

Gram’s stain on each culture: observeGram s stain on each culture: observe morphology and Gram result

Malachite Green stain on all cultures: observe presence or absence ofobserve presence or absence of endospores

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Gram staining of bacteria (a type of differential stain)


(a type of differential stain).

Sample from the mouth, showing Gram positiveshowing Gram positive and Gram negative bacteria.



The Gram’s Stain – a differential stain

Slonczewski and Foster: Figure 2-22 Slonczewski and Foster: Figure 2-23 10


Lab 1 part 2Lab 1 part 2

Work in groups of 4Work in groups of 4

Inoculate all cultures into thioglycollateInoculate all cultures into thioglycollate agar

Inoculate all cultures into phenol red brothbroth

Catalase test on culture agar slants11

Catalase test on culture agar slants

Oxygen-related growth zones in a standing test tube.Bio 2EE3 Lab 1 pre-lab talk

Thioglycollate agar

Inoculate with a needle to the bottomneedle to the bottom of the tube.

Ob hObserve where growth occurs

Indicates oxygen requirements of that organism


organism

Clinical tests based on fermentation.Bio 2EE3 Lab 1 pre-lab talk

Phenol red broth – pH indicator

Different fermentationDifferent fermentation pathways result in acid and/or gas production

Gas collects in the Durham tube


Generation and destruction of reactive oxygen species (ROS)


(ROS).



Lab 1 part 3: to do individuallyLab 1 part 3: to do individually

Plate an environmental sample to obtainPlate an environmental sample to obtain single colonies: Soil, water

Sample from your teethSample from your teethYogurtFingersFingersCultures A – E (before the catalase test!)the catalase test!)

NOTHING PATHOGENIC!15

NOTHING PATHOGENIC!

Dilution streaking technique.Bio 2EE3 Lab 1 pre-lab talk



AssessmentAssessment

Complete the informal lab reportComplete the informal lab report

Share results but the lab report must beShare results but the lab report must be done individually

Due ONE week after the lab – dropboxes

Morning labs by 12 noonAfternoon labs by 4pm

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Afternoon labs by 4pm

2ee3 lab #1 prelab

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