1. The Examination of Bacterial Colonies in Selected Environments
Bacterial Diversity
The Examination of Bacterial Colonies in Selected Environments
By Lara Hartman and Daniel Arbeider

2. Purpose Explore the bacterial diversity found in:
Air
Raw Chicken
Soil
Pond Water
Washed & Unwashed Hands
Library Table
Establish which environment supports the greatest diversity of bacteria.
Compare the data generated to determine if our hypothesis is supported.

3. Hypothesis
Pond water will contain the greatest diversity of bacteria when compared to other observed environments.

4. Methods Label each Petri dish according to the environment tested.
To isolate bacterial colonies from the soil, pond water, chicken, and the PSU library table the “Streak Plate method” was used.
For the air sample the lid will be removed for the duration of the experiment.
For washed and unwashed hands, a thumb will be pressed on the surface of the agar.
Incubate all plates for 1 week at 22 C.

5. Air Size Shape Margin Surface Color A 15 mm Irregular Lobate Smooth
Size
Shape
Margin
Surface
Color A
15 mm
Irregular
Lobate
Smooth
Milk-White B
5 mm
Round
Concentric
Pale Yellow C
6 mm
Curled
White D
Off-White E
14 mm
Contoured
Mustard

6. Raw Chicken Size Shape Margin Surface Color A 1 mm Punctiform Lobate
Size
Shape
Margin
Surface
Color A
1 mm
Punctiform
Lobate
Wrinkled
Off-White B
7 mm
Irregular
Contoured
Clear

7. Soil Size Shape Margin Surface Color A 6 mm Irregular Lobate Smooth
Size
Shape
Margin
Surface
Color A
6 mm
Irregular
Lobate
Smooth
Off-White B
7 mm
Filamentous
Contoured
White C
30 mm
Clear
F u n g u s

8. Pond Water Size Shape Margin Surface Color A 3 mm Round Smooth
Size
Shape
Margin
Surface
Color A
3 mm
Round
Smooth
Off-White B
10 mm
Irregular
Lobate
Contoured

9. Washed and Unwashed Hands
Size
Shape
Margin
Surface
Color A
59 mm
Irregular
Wavy
Smooth
Off-White B
7 mm
Filamentous
Contoured
White C
13 mm
Lobate

10. Library Table Size Shape Margin Surface Color A 15mm Irregular Lobate
Size
Shape
Margin
Surface
Color A
15mm
Irregular
Lobate
Smooth
White B
6 mm
Round
Wavy
Concentric
Yellow C
11 mm D E
3 mm
Orange
F u n g u s

11. Data Interpretation
After one week, observations were made of the colony morphology of the different bacterial species in each environment.
Charts were constructed to compare the diversity and abundance of bacteria in the various environments.
Our data clearly showed that the hypothesis under investigation was not supported; however, it is reasoned that the pond water sample was not the best representation of aquatic life. In our next experiment all layers, top – middle-bottom, will be analyzed.

12. Escherichia coli Role: Pathogenic effects:
Produces Vitamin K in the intestinal tract.
Pathogenic effects:
Human urinary tract infections
Diarrhea
Pneumonia (linked)
Meningitis (linked)

13. E.coli How E.coli infects: Treatments: Studies:
E.coli and how it infects – Part 1
E.coli and how it infects – Part 2
E.coli and how it infects – Part 3
Treatments:
Antibiotics are not recommended. (May cause shock)
Studies:
Antibiotic treatment increases risk of urinary tract infections from 8% (no treatment) to 56% (antibiotic treatment).
E.coli develops antibiotic resistance quickly.

14. E.coli Antibiotic Dose Zone of Inhibition Sensitivity 1 Steptomycin
Antibiotic
Dose
Zone of Inhibition
Sensitivity 1
Steptomycin
10 mg
5 mm
Sensitive 2
Penicillin
0 mm
Not Sensitive 3
Erythromycin
15 mg
3 mm 4
Tetracyclin
30 mg
7 mm 5
Kanamycin 6
Chloramphenicol
12 mm
Very Sensitive 7
Nalidixic Acid
11 mm 8
Novobiacin
Control

15. Sources
Carter Brown, M.E., and J.G. Morgan. Investigating Biology: A Laboratory Manual for Biology. San Francisco: Benjamin Cummings, 2002.
Dennis Liu, Ph.D., and B. Brett Finlay, Ph.D. Enteropathogenic E. coli Infection Mechanism. Retrieved November , from
Craig S. Wong, Srdjan Jelacic, Rebecca L. Habeeb, Sandra L. Watkins, Phillip I. Tarr; Early Release article, The New England Journal of Medicine; May 23, Retreived November 2, 2004, from