Identification of Bacteria by Enzymatic Activity

1. Identification of Bacteria by Enzymatic Activity Courtney Ballinger Undergraduate Student (Health Science Concentration), Department of Biology, Tennessee Technological University, Cookeville, TN 38505

2. Introduction • Bacteria are like any other cells; they are powered by biochemical reactions known as metabolism (Tondo et al 2004). • The main purpose of metabolism is to generate energy and use it for the work of the cell or bacteria (Kilian 1978).

3. Introduction (continued) • Metabolic reactions are performed by enzymes and with each individual step throughout the pathway require the use of a different enzyme (Krivobok et al 2003). • Different bacterial species use different pathways (King et al 1978).

4. Introduction (continued) • The complement of enzymes found in a particular bacterium can be used as a biochemical fingerprint to identify it (Goss 2006). • Objective: Identify various bacteria so the identification of unknown bacterium is possible using methods from Biology 3230 Health Science Microbiology Laboratory Manual.

5. Introduction (continued) • Hypothesis: I will be able to identify an unknown bacterium using 6 enzyme tests on less than 10 organisms. • Null Hypothesis: The unknown bacterium will be identified by using more than 10 organisms.

6. Methods and Materials • The methods used in this experiment are the ones located in Sue Goss’s Biology 3230 Health Science Microbiology Laboratory Manual. • Experimental Design • Statistics show that by using enzyme activity identification of unknown bacteria is capable with less tests and time compared to standard procedures commonly used.

7. Results • The identification of various unknown bacteria using (Table 1) was successful. • The graph (Figure 1) shows the success rate of identifying unknown bacteria by this process. • Photos of some of the tests are shown (Figures 2-4).

8. Results (continued) Figure 2. Positive DNAse Test Figure 3. Gram Stain Figure 4. Catalase Test Reactions

9. Discussion • My results proved that my hypothesis of being able to identify unknown bacteria using only six enzyme tests on less than ten organisms can be accepted. • The null hypothesis of having to use more than ten organisms can be rejected.

10. Discussion (continued) • My results show that since bacteria use different metabolic pathways, enzyme tests are useful in identification (King et al 1978). • Metabolic reactions are performed by enzymes, so the detection of what unknown you have is indicated by the result of the enzyme test (Krivobok et al 2003).

11. Discussion (continued) • Energy is generated from metabolism and by using certain tests it assisted in the identification of the unknown bacteria (Kilian 1978). • The enzymes present in the bacteria did serve as a biochemical fingerprint for identification (Goss 2006).

12. Discussion (continued) • The biochemical reactions of bacteria are proven to be a successful way to identify unknown bacteria (Tondo et al 2004). • Overall the results that I collected positively correlated with the previous work and information that researchers in the past have collected on this topic.

13. Conclusions • Fast identification of unknown bacteria is possible with the assistance of enzyme reactivity. • Using the identification of other bacteria and enzyme reactivity, it allows unneeded tests to be eliminated from the normal routines commonly used.

14. Conclusions (continued) • This procedure of identification can benefit people throughout the medical field. • With the assistance of enzyme tests this method could save time, money, and possibly lives.