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New This Week: Gram (+) Bacteria ID Review Gram + and - tests. Last week:. Exp 62: ID of Human Staph. and Strep. Pathogens. Lab Two, Part 2: Blood and MSA, pg 429 Lab Two, Part 1: Coagulase Test, pg 429. Physical Factors Exp 15: Temperature Exp 16: pH Exp 17/18: O 2 Requirements. - PowerPoint PPT Presentation
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Lab Two, Part 2: Blood and MSA, pg 429
Lab Two, Part 1: Coagulase Test, pg 429
Exp 29: Catalase Test
Physical Factors
Exp 15: Temperature
Exp 16: pH
Exp 17/18: O2 Requirements
Week 10WWeek 10W
Exp 62: ID of Human Staph. and Strep. Pathogens
Lab Two, pg 196add H2O2
Last week: New This Week: Gram (+) Bacteria ID Review Gram + and - tests
New This Week: Gram (+) Bacteria ID Review Gram + and - tests
Gram staining practice
Syllabus Corrections
Pg 3– Week 12: Assign. #7 due– Week 13: Assign. #6 due (not # 8)
Pg 8– Week 11: Prepare Assign. #7 (not #6)– Week 12: Quiz 9 covers definitions from
Assign. #7 (not #6)
: Prepare Assign. #6 (not #8)
Exp 62: ID of Human Staph. And Strep. Pathogens: Blood and MSA Review
An MSA plate with Micrococcus sp. (1), Staphylococcus epidermis (2) and S. aureus (3) colonies.
Red blood cells on an agar plate are used to diagnose infection. On the left is a positive Staphylococcus infection, on the right a positive Streptococcus pyogenes culture.
Exp 62: ID of Human Staph. And Strep. Pathogens:
Coagulase Test Coagulase reacts with the fibrinogen in plasma,
and precipitates into fibrin cells clump together , look “lumpy”.
Test useful for differentiating Staphylococcus aureus from other Gram positive, catalase + cocci.
Any degree of clotting, from a loose clot suspended in the plasma to a solid, immovable clot is a positive result. Plasma which liquid remained is a negative result.
Exp 62: ID of Human Staph. And Strep. Pathogens:
Coagulase Test
fibrin
Exp. 29: Catalase Test
o Hydrogen peroxide (H2O2) accumulation is toxic to cells. o Presence of bubbling or foaming when adding H2O2 to a culture, indicates that the hydrogen peroxide is being broken down by catalase, with the release of oxygen gas.o Bubbling = pos. catalase o Absence of foaming/bubbling= neg. catalase (catalase is not present in cell)
Results To ID Gram Positive Bacteria
Notation
MICROORGANISM
Staph. epidermidis
(SE)
Staph. aureus
(SA)
B. subtilis (BS)
Strep. salivarius (SS)
M. luteus
(ML)
Morphology
shape/ arrangement cocci/ cluster
cocci/ cluster
rods cocci/ chaincocci/ cluster
TSA (cultural characteristics)
color, size, form, margin,
elevation, texture
+/- growth ■
MSAMF or NMF/
color
Blood Agar (cultural characteristics)
color, size, form, margin,
elevation, texture
Blood Hemolysis
У α β
Catalase Activity
+/- catalase ■
Coagulase Actvity
+/- coagulase
Seafloor bacteria on ocean-bottom rocks are more abundant and
diverse than previously thought.
Grand Prismatic Spring, Yellowstone National Park (thermophiles)
Below Freezing Salt Water Pockets in Antarctica
Bacteria Around Nuclear Reactors
Biofilm build-up on tank walls—
guaranteed tocontaminate any fuel
Exp 15: Physical Factors: Temperature
Exp 16: Physical Factors: pH of the Extracellular Environment
Exp 17/18: Physical Factors: Atmospheric Oxygen RequirementsCategory Oxygen Requirement Production of
Catalase
Obligate Aerobe
Requires oxygen and oxygen is not toxic to it. Produces catalase.
Microaerophile Requires oxygen at low levels and atmospheric levels of oxygen are toxic to it. Prefers oxygen
at a concentration lower than 10%.
Produces catalase
sometimes.
Facultative Anaerobe
Uses oxygen preferentially when oxygen is present, but can grow without oxygen (slower growth than with oxygen). Oxygen is not toxic
to it.
Produces catalase.
Obligate anaerobe
Does not use oxygen and oxygen is toxic to it. No catalase production.
Aerotolerant Does not use oxygen, but oxygen is not toxic to it.
Produces catalase.
How is distribution of growth affected by atmospheric oxygen ……..?
TABLES 5 & 6Exp. 17/18: Atmospheric Oxygen RequirementsMedia: 3Thioglycollate broth 3 NUT brothCulture: EC, ML & CSProcedure: (refer to pg. 127)• Label ea. tube w/org & media.• Inoculate each org. in thioglycollate and NUT broth.• Place thioglycollate tubes in anaerobic GasPack chamber.•Incubate all at 37oC for 24 hrs.
Week 10WWeek 10W
GLU SUC LAC
TABLES 1 & 2
Exp 15: Temperature
Media: 12 NUT slant
Culture: SA , ML, BST
Procedure: (refer to pg. 111)
• Label each tube w/ org. and temp.
• Inoculate with loop 4 slants w/each org.
• Incubate 1 slant from each org. at either 4oC, 25oC, 37oC, and 55oC for 24 hrs.
TABLES 3 & 4
Exp 16: pH of the Extracellular Environ.
Media:
2 NUT broth @ pH 2
2 NUT broth @ pH 5
2 NUT broth @ pH 7
2 NUT broth @ pH 9
Culture: EC & SA
Procedure: (refer to pg. 116)•
Label each tube w/ org. and pH.
• Inoculate with ea. org in various pH tubes.
• Incubate at 37oC for 24 hrs.
BST- Bacillus stearothermophilusCS- Clostridium sporogenes
Gram staining practice