Preview

Unknown Project Microbiology

Good Essays
Open Document
Open Document
698 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Unknown Project Microbiology
Tanti Lim
Thurs AM

Unknown Project

I. Introduction
The purpose to this lab was to isolate and identify two unknown bacteria from a mixed culture provided to us. This study was done by applying all of the methods that have been instructed on thus far in microbiology laboratory class. Each test performed, provided us with some key information about the unknown microbes in question .
The identification of unknown bacteria is a time honored part of microbiology courses. It will challenge knowledge and skill in performing laboratory techniques, ability to critically evaluate the information obtained from these techniques, and ability to effectively communicate the information.
There are many reasons for knowing the identity of microorganisms. The reasons range from the knowing the causative agent of a disease in a patient, so as to know how it can be treated, to knowing the correct microorganism to be used for making certain antibiotics. This study was done by applying all of the methods that have been learned so far in the microbiology laboratory class for the identification of an unknown bacterium.

II. Results
Unknown A a. The unknown is a gram negative bacilli
Upon performing a gram stain on a colony from a streak of the unknown bacteria, at 100x, the bacteria stains negative for the gram stain. In addition, the structure of the bacteria is bacilli. b. The unknown is a facultative anaerobe
A small amount of bacteria was added to a tube of fluid thioglygollate media, which permits the of a wide variety of bacteria and also allows the determination of the oxygen requirements of an organism. c. The unknown is nonmotile
The media was inoculated with a single stab to the center of the tube and incubated. After incubation, the growth was restricted to the stab line, the bacteria is nonmotile. d. The unknown is no capsule formed
The bacteria was removed from a single loopful of broth from the tube and streak it into

You May Also Find These Documents Helpful

  • Powerful Essays

    The purpose of the unknown bacteria lab assignment was to select an unknown bacteria culture and, through a series of metabolic tests, identify which bacteria genus resided in the pure culture received. A nutrient broth inoculated with bacterial culture (numbered 45, henceforth referenced as U45) was selected and a streak plate was made to isolate a pure culture for use throughout the assignment.…

    • 1738 Words
    • 7 Pages
    Powerful Essays
  • Good Essays

    There are many reasons for identifying an unknown bacterium. The reasons range from medical purposes, such as determining if the unknown could cause ailments in living things or knowing what microorganisms are needed to make antibiotics to other purposes such as knowing the exact microorganism has to be used to make certain foods. This experiment was done by applying methods in order to identify an unknown bacterium.…

    • 481 Words
    • 2 Pages
    Good Essays
  • Better Essays

    Unknown Lab Report

    • 2145 Words
    • 9 Pages

    The tests performed on the unknown bacteria cultures were all used to determine the identity of the bacteria. Each of the tests performed provided some key information about the bacteria in question and how it functions. Not all of the tests were performed on every culture, however, as some of the tests were used only for gram (+) or gram (–) bacteria, while others were even more specific and used only for cocci bacteria. The tests performed and what constitutes a positive and negative test are as follows.…

    • 2145 Words
    • 9 Pages
    Better Essays
  • Better Essays

    Micro Unknown Lab Report

    • 2042 Words
    • 9 Pages

    The purpose of this lab was to identify an unknown bacteria culture using differential tests. The identification of the unknown culture was accomplished by identifying the bacteria based on its specific metabolic characteristics and morphology. It is suggested that culture 11 is a sample of Enterobacter aerogenes.…

    • 2042 Words
    • 9 Pages
    Better Essays
  • Good Essays

    Microbiology Unknown

    • 2745 Words
    • 11 Pages

    The most important fact that should come out of microbiology is the “profound influence” that microorganisms have on the aspects of earth (Cowan, 2012).…

    • 2745 Words
    • 11 Pages
    Good Essays
  • Better Essays

    The purpose of the following study is to determine where the two unknown bacteria acquired in Microbiology lab should be classified in regards to temperature, pH level, and osmoregularity. It is important to classify bacteria in order to identify them. Identification of bacteria is important because they are not only useful but potentially dangerous as well. The identification of bacteria can lead to breakthroughs in healthcare regarding treatment of old and new diseases alike. Identifying bacteria can also be used in many other areas from better crop production through microbial pesticides to biological warfare. Their uses are endless as are their abilities to evolve and adapt to changing environments. That is why it is so important to be able to identify microorganisms. This study was conducted using techniques and experiments learned in microbiology lab that were used to classify the two unknown bacteria.…

    • 862 Words
    • 4 Pages
    Better Essays
  • Better Essays

    Mystery Microbe

    • 2499 Words
    • 10 Pages

    Introduction: Being able to identify a particular bacterial species is important. It is very useful in knowing its risk of toxicity to humans or animals, its resistance or susceptibility to antibiotics, and determining how to control its growth or kill it altogether. The purpose of these procedures is to discovery the identity of an unknown microbe by observing its reactions to a barrage of chemical and physical tests. Different microorganisms react in different ways, due to their function, digestibility, morphology, chemical make-up and other details. By observing the responses to these tests performed in a particular sequence, some can be eliminated as possibilities and others require further investigation.…

    • 2499 Words
    • 10 Pages
    Better Essays
  • Good Essays

    Unknown Lab Report

    • 1149 Words
    • 5 Pages

    Prepare two slides for gram staining and viewing under a microscope. {Either my gram-stain slides were bad or the microscopes I chose for viewing were not good. No bacteria were found under the microscope.}…

    • 1149 Words
    • 5 Pages
    Good Essays
  • Better Essays

    In this lab experiment we did several test to determine what our unknown bacteria was. To determine this we recorded the results of how the bacteria reacted to different media. Depending on the results of each test we could narrow down the different bacteria to determine what our unknown is. This experiment will also determine if our bacteria is a fermenter of sugars and if it is catalase positive. If the bacteria is a fermenter they will use the sugars to make ATP. If the bacteria is a fermenter of lactose/sucrose the EMB plate we used will “clearly differentiate between the colonies of lactose fermenting and non-fermenting microbes. In the same medium sucrose was also included to differentiate between coliforms that were able to ferment sucrose more rapidly than those that were unable to ferment sucrose” (Cheeptham & Lal, 2007).…

    • 1370 Words
    • 6 Pages
    Better Essays
  • Good Essays

    Unknown Lab Report

    • 891 Words
    • 4 Pages

    An unknown bacterium was handed out by Dr. Honer. The appropriate tests were prepared and applied. The first procedure that was done was the gram stain. Under a microscope, if the gram stain is purple, the bacterium is gram positive, if the stain is red, it is gram negative. The next test was the fermentation tests for glucose, sucrose and lactose. If an organism is able to ferment the carbohydrate, there will be acid produced, which will turn the broth yellow. Homofermentation shows that only one product was produced-acid. Other organisms will carry out heterofermentation, the presence of acid and gas. If the organism is unable to ferment the sugar in the tube, there will be no change in the orange/red color of the broth and will be considered alkaline. The following tests that I performed were tests for methyl red and vogues proskauer in SIM media. A positive methyl red test indicates a mixed acid fermentation and would turn the organism’s broth red, if no color presents, it is negative. A positive vogues proskauer test indicates fermentation to neutral products and will turn the broth red, if no color presents, it is also negative. Stab inoculating the SIM media for these tests will also show if the organism produces sulfur or indole and if it is motile. If sulfur is present, then the medium will be black, if it produces indole, the medium will be red, and if it is motile, there will be growth throughout the tube. I also grew the organism on MacConkey agar. After inoculation, visible colonies may or may not be present.…

    • 891 Words
    • 4 Pages
    Good Essays
  • Good Essays

    The objective of this experiment was to identify an organism from a mixture of two unknown bacterial species. In order to accomplish this, I first plated my unknown mixture on Tryptic Soy Agar (TSA), Columbia Naladixic Acid (CNA), and MacConkey’s Agar (MAC) plates. After 48 hours of incubation, it was unclear that two different bacterial colonies had grown on my TSA plate. Only one type of colony was evident. However, it was apparent that I had successfully isolated two different bacterial species by examining my MAC and CNA plates. Only one type of colony had grown on my MAC plate indicating a gram negative species, which I chose to be organism A. Similarly, only a single type of colony had grown on my CNA plate, indicating a gram positive species, which I chose to be organism B. By performing a gram stain on the two colonies I was positive they were two different species because organism A were gram negative rods in single arrangement and organism B were gram positive cocci arranged in irregular clusters. I ran a catalase test on both organisms; organism A was catalase positive while organism B was catalase negative. I also performed a cytochrome oxidase test on both organisms; again, organism A was oxidase positive while organism B was oxidase negative. Then I decided I would run the biochemical tests on organism B. I observed that organism B was non-motile and did not produce endospores. With these results, I narrowed down the possible species to Enterococcus faecalis, Enterococcus faecium, Lactococcus lactis, Leuconostoc mesenteroides, Pediococcus parvulus, and Streptococcus mitis.…

    • 784 Words
    • 4 Pages
    Good Essays
  • Good Essays

    Unknown Lab Report

    • 638 Words
    • 3 Pages

    Unknown #25 had the following morphology on a streak plate: medium sized butyrous cream colored colony. Gram-staining was utilized as a first step to differentiate between gram-positive and gram-negative. After determining that it was a Gram negative single bacillus, biochemical tests performed and their purpose and results are shown in table and flow chart form.…

    • 638 Words
    • 3 Pages
    Good Essays
  • Better Essays

    Microbiology Unknown

    • 1005 Words
    • 5 Pages

    By slowly narrowing down the bacteria by each test, I will be able to conclude the unknown bacteria by its special characteristics.…

    • 1005 Words
    • 5 Pages
    Better Essays
  • Better Essays

    Nester, Eugene W., et al. Microbiology A Human Perspective. Sixth Edition. Mc Graw-Hill Companies 2009.…

    • 1118 Words
    • 5 Pages
    Better Essays
  • Better Essays

    Unknown Lab Report

    • 1022 Words
    • 4 Pages

    The professor gave out the unknown specimens. It contained one-­‐gram positive and one-­‐gram negative bacteria from the given list. I was assigned unknown A. The process of identification was achieved by utilizing procedures learnt during the semester. Procedures were followed as stated in the lab manual (1). Since the sample contained two unidentified bacteria, the first step was to isolate each bacterium using streak plate technique. Tryptic Soy Agar (TSA) plate, and differential media such as mannitol salt and Eosin methylene blue (EMB) were used for isolation streak technique. This step is imperative because the bacteria need to be separated and isolated before they can be identified. Moreover, gram staining was used to understand the basic morphology of these bacteria. As these plates were incubated and grown, the presence of two separate bacteria colonies was visible. The colonies from the mannitol salt were used to incubate a TSB broth to grow the gram-­‐positive culture. The purity of this broth was tested using gram-­‐staining technique. A circular colony from the TSA plate was used to…

    • 1022 Words
    • 4 Pages
    Better Essays