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Cover page (Use this specific format)

RESEARCH REPORT

IDENTIFICATION OF UNKNOWN MICROBES

Course: Savannah State University – 3321L / 2020 Spring

Section: 1 (1 PM) or Section 2 (4 PM) (highlight one)

Group Name (type your group name): Group X

Submission option: Individual or Group (*up to 4 members per repot) (highlight one)

Authors (Student name and 915) who contribute to write this report

1. Student A / 915-XXXXX

2. Student B / 915-XXXXX

3.

4.

Introduction:

It is imperative to understand why one would want to differentiate between multiple types

of bacteria. In order for a person to receive proper treatment for a certain pathogen, the microbe

has to be first identified. This whole process is done for the reason that different treatments may

work effectively against one microbe, while it may prove to be ineffective against another. Also,

microbe identification is significant in processing of certain foods and development of antibiotics.

The overall purpose and aim of this investigation is to identify an unknown sample of bacteria

retrieved from the oral cavity of a group member. The following study was performed by following

a series of protocols and techniques listed in the lab manual given from Professor Takayuki Nitta

(Reference).

Materials & Methods

First, a sample was obtained from the oral cavity of a group member by using a sterile

cotton swab, and inoculated onto a T-soy agar plate. In order to maintain the freshness of the

unknown sample, the group changed the T-soy media of the bacteria by inoculating the bacteria

onto a new T-soy agar plate every 1 – 2 weeks.

The first test conducted was the Gram-staining test, —————————————.

Or

To identify the microbe isolated from XXXX, a series of tests are completed. The summary for

the reagents, procedures used in the tests are shown in Table 1.

Table 1 Summary of methods to characterize the bacteria isolated from forehead.

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Test name Purpose Reagents/

Materials

Procedures

Gram stain 1. To determine shape of bacteria cells

2. To determine Gram reaction of bacteria

Cristal violet

Iodine

Alcohol

Safranin

After fixation of the samples

smeared on the microslide, the

bacteria were exposed to cristal

violet, iodine, alcohol and

safranin, sequentially. The

bacteria on the slide were

observed by compound

microscope.

Colony shape To characterize shape of

bacterial colony

Dissecting

microscope

Observe bacterial colony by

microscope

e.t.c

Students need to list all methods used to identify the bacteria

Results

The unknown microbe appeared to form opaque yellow colored colonies when plated. Ultimately,

the unknown microbe was a gram-positive microbe with a staphylococcus type of morphology. It

was able to breakdown hydrogen peroxide, survive in a region of high salt concentration, coagulate

blood plasma, and also able to ferment mannitol. Table 2 below lists the tests performed along

with reagents, and also the observer’s observations and results, while Figure 1 shows the process

in which tests were completed to make the final deduction.

Table 2. Summary of results obtained through the tests Test Observations Results/Interpretation

Gram stain Violet colored clusters of spheres Coccus-shaped and Gram-positive

Endospore stain No green was stained on slide and

grape-like clusters were seen

Cannot form endospores and the

morphology is staphylococcus

Catalase Bubbles appeared instantly Has ability to catalyze breakdown

of hydrogen peroxide

Indole test Pale yellow color Negative indole test

MSA Growth / Media became yellow Halophiles and ferment mannitol

e.t.c.

Students need to list all results obtained through the experiments

• Insert figures of your complete diagnostic key in section “Results” Alternatively cite the figures of diagnostic key in section “Results” and cite the figures

in the main text.

(e.g. To identify the isolated microbe, we analyzed the diagnostic key. The complete diagnostic

key was inserted in this section (Fig. 1) or attached separately (Fig. 1).

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Fig. 1. Diagnostic key for Gram Positive and Negative bacteria

(Here is one page only, but 4 pages of the completed key are required for full credits)

Discussion & Conclusion

In conclusion, it is deduced that the unkown bacteria retrieved is XXXXXXX. This

conclusion was reached due to the parallel in test results of the group’s data and that of Gloria et

al, who asserts that S. aureus is a gram positive bacterium which displays the characteristic of

clumping (Gloria et al, 2011). She then goes on to state that S. aureus is a “gram-positive

bacterium…that is also able to ferment glucose…produces catalase, nitrate, and coagulase” (Gloria

et al, 2011). According to Table 1 and Fig. 1, the tests conducted all resulted in the same findings.

Also, the unknown sample proved to be indole negative and had an inability to create spores.

(e.g. When you have additional tests to identify microbes or that were not completed)

Unfortunately, the group was not able to complete oxidation and fermentation tests because

XXXXXXXXX. In order to combat this problem in the future, the different microbiology lab

classes should be separated more carefully, and also, the group should be sure to label its materials

better.

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References

1. “Microbiology (BIOL3321L) Laboratory Manual Fall 2014”. Nitta, Takayuki. (Fall 2014). 1st edition. Pgs. 1-XX. Print.

2. “Gram Stain of Staphylococcus aureus from a wound infection” Gloria D., Lewis Tomalty. American Society for Microbiology. August 22, 2011.