The Identification of Two Unknown Bacteria Mixtures Through the Method of Characteristic Testing and Elimination Khoa Vuong TA: Charlie Roll Micro 3301 4/11/24.
Abstract: There is a surplus amount of microorganisms that are out there in the world. A single swab of any surface, including the human body, will yield many different types of microorganisms. Once grown on a nutrient-rich medium, the identification of these microorganisms can be made by isolating pure colonies and performing and using various plates and broth and recording its characteristics. It is important to understand and characterize each microorganism, behavior, reaction, and appearance for future purposes. In this experiment, the identification of two unknown bacteria was …show more content…
It ranges from their size, metabolism activity, and their reproduction rate. The reason why it is important to be able to classify and identify microorganisms is because of pathogenic strains that can be potentially harmful to the public and ourselves. Typically, microorganisms are identified through various streak plate methods and under a microscope. The streak plate method helps isolate wanted pure colonies of bacteria to observe their characteristics under the microscope. But how does one tell the difference between different strains of bacteria of the same genus and species? One method that is used in the realm of foodborne pathogens is through polymerase chain reaction (PCR). PCR works by heating the DNA strand to separate the DNA, selecting a specific DNA fragment from a unique pathogenic microorganism, and if the presence of that selective genetic strand is in abundance through PCR, it can be concluded that that particular bacteria is present in the food product that is being tested …show more content…
Initially, it started with three plates, the Tryptic Soy Agar (TSA), the Colistin-Nalidixic Acid agar (CNA), and the MacConkey plate (MAC). Each plate had growth of coccus-shaped colonies. Through Gram staining, it was observed that the colonies on the TSA plates contained both gram-negative bacteria and gram-positive bacteria. Gram-positive bacteria were present on the CNA plate, and only gram-negative on the MAC plate. An observation was noted on the MAC plate, pink precipitation was observed on the bacteria colonies indicating that the bacteria can ferment lactose. White convex coccus colonies with no hemolytic activity were observed on the CNA plate. DNase plates were also used for the unknown bacteria. This plate is used to determine if the bacterium can hydrolyze DNA and for the two bacterium, it was found that they are DNase negative with no halo observed on the plate. Blood Agar Plate (BAP) was used to determine the hemolytic activity of the gram-positive bacteria. Similarly to the CNA plate, no hemolytic activity was observed indicating that the bacterium shows gamma hemolysis characteristics. A tube of Triphenyl Tetrazolium Chloride soft agar deeps (TTC Deep) was used for each unknown organism which tested for the motility of the bacterium. The observation recorded showed the gram-positive bacteria had no motility, while the gram-negative bacteria
Abstract: There is a surplus amount of microorganisms that are out there in the world. A single swab of any surface, including the human body, will yield many different types of microorganisms. Once grown on a nutrient-rich medium, the identification of these microorganisms can be made by isolating pure colonies and performing and using various plates and broth and recording its characteristics. It is important to understand and characterize each microorganism, behavior, reaction, and appearance for future purposes. In this experiment, the identification of two unknown bacteria was …show more content…
It ranges from their size, metabolism activity, and their reproduction rate. The reason why it is important to be able to classify and identify microorganisms is because of pathogenic strains that can be potentially harmful to the public and ourselves. Typically, microorganisms are identified through various streak plate methods and under a microscope. The streak plate method helps isolate wanted pure colonies of bacteria to observe their characteristics under the microscope. But how does one tell the difference between different strains of bacteria of the same genus and species? One method that is used in the realm of foodborne pathogens is through polymerase chain reaction (PCR). PCR works by heating the DNA strand to separate the DNA, selecting a specific DNA fragment from a unique pathogenic microorganism, and if the presence of that selective genetic strand is in abundance through PCR, it can be concluded that that particular bacteria is present in the food product that is being tested …show more content…
Initially, it started with three plates, the Tryptic Soy Agar (TSA), the Colistin-Nalidixic Acid agar (CNA), and the MacConkey plate (MAC). Each plate had growth of coccus-shaped colonies. Through Gram staining, it was observed that the colonies on the TSA plates contained both gram-negative bacteria and gram-positive bacteria. Gram-positive bacteria were present on the CNA plate, and only gram-negative on the MAC plate. An observation was noted on the MAC plate, pink precipitation was observed on the bacteria colonies indicating that the bacteria can ferment lactose. White convex coccus colonies with no hemolytic activity were observed on the CNA plate. DNase plates were also used for the unknown bacteria. This plate is used to determine if the bacterium can hydrolyze DNA and for the two bacterium, it was found that they are DNase negative with no halo observed on the plate. Blood Agar Plate (BAP) was used to determine the hemolytic activity of the gram-positive bacteria. Similarly to the CNA plate, no hemolytic activity was observed indicating that the bacterium shows gamma hemolysis characteristics. A tube of Triphenyl Tetrazolium Chloride soft agar deeps (TTC Deep) was used for each unknown organism which tested for the motility of the bacterium. The observation recorded showed the gram-positive bacteria had no motility, while the gram-negative bacteria