Identifying the Unknown Bacteria: Bacillus cereus Brittany Moy Coastline Community College Abstract Bacillus cereus is a Gram-positive, facultative aerobic, spore-forming, rod-shaped bacterium that is widely distributed among the environment. Introduction The reason for identification of unknown bacteria was to help students recognize different bacteria through different biochemical tests and characteristics. This is important in the medical field because identification of unknown bacteria can help treat a patient by knowing the contributing source of a disease. Also, knowledge of different bacteria helped others make antibiotics that are used today. Bacillus cereus, a commonly occurring pathogen which can …show more content…
Results There are many reasons for identifying an unknown bacterium. The purpose of this exercise was to identify an unknown bacterium from a liquid culture. We chose our unknown bacteria from a rack of test tubes with several different species of bacteria inside. I wanted to pick an unknown bacteria with a number easy to remember so I pick the test tube labeled “745”. Procedures were followed as stated in the lab manual written by Dr. Pedro J.A. Gutierrez. Lab Day 1: After receiving my unknown bacteria, I streaked a TSA plate and incubated at 37°C for 48 hours. I then picked a single colony from the plate with my sterile loop and streaked a TSA slant and labeled it “Working Stock”. I did the same with another TSA slant and label the second one “Back-up Stock”. This would be the samples I used to complete the following procedures through the next four weeks to determine my unknown bacteria. Lab Day 2: The first procedure that was done was a simple stain to identify the bacterial shape. Bacteria tends to be transparent, so a stain must be use to color the cells of the bacteria so it can be viewed under a compound microscope. After heat-fixing three separate loopfuls of my unknown bacteria onto a slide, I used Methylene blue, Safranin, and Crystal violet to stain the three different samples. After rinsing the slide and observing my finding under the microscope, I
This organism is commonly found in soil and food; certain strains can cause foodborne illness while other strains are used as probiotics and are found in human digestive tracts, which makes sense since this environmental was sampled from the handle/lock mechanism of a public toilet stall (Wong, et. al. 1998, BAM 2012). Furthermore, B. cereus is known to be resistant to the effects of alcohol, and if an alcohol-based cleaner was used in the bathroom prior to the sampling for this experiment, it would explain why the bacteria was still present after the bathroom was cleaned, especially if the sample location – toilet stall lock – was cleaned as well (“Notes from the Field…” 2011).
B. cereus is known as a bacterium that tends to produce toxins in the body. Depending on the type of strain, this bacterium can be
Bacterial foodborne pathogens are serious threats facing public human health and worldwide economies. C. jejuni, C. coli, S. enterica subspecies enterica, L. monocytogenes, Shiga toxin producing E. coli, S. aureus, C. botulinum, and Shigella species are considered the major foodborne bacterial pathogens causing million cases of morbidities and mortalities per year all over the world. Furthermore, the emergence of multidrug-resistant toxin-producing foodborne bacterial pathogens as enterotoxigenic MRSA, is considered a supreme threaten risk facing human health and implicated in foodborne outbreaks. In addition, C. botulinum neurotoxins are the most potent known foodborne toxin. Moreover, L. monocytogenes can colonize food processing environments for years in the niches.
After gram staining the sample, Escherichia could be ruled out as it is gram negative. The next step would be to explore the shape and cell structure of the two remaining bacteria types. Bacillus shaped like a rod and divides to form a chain. It also has
Bacteria can be found on numerous locations of the human body, while some are beneficial to human health others are not. Upper respiratory tract infections for example can be cause by pathogenic bacteria. Left untreated, respiratory infections can be harmful or even fatal in some cases. Therefore, identifying the cause of the infection is paramount. Knowing the target would allow the correct treatment methods to be utilized, such as the use of an effective antibiotic. The purpose of the experiment was to identify a bacteria of interest that has presumably caused an upper respiratory tract infection. Furthermore, the goal was to use as few test as possible to produce quick yet accurate results which could be vital in a real world situation
In the medical field which I am going into, it is very important to be able to identify bacteria. By identifying bacteria, we can prevent, diagnose its presence and determine what is the appropiate treatment to treate the diseased caused by them. For example, if a patient is complaining of a sore throat we can take a sample of the throat to determnne what bacteria if any is causing the pain. Once the bacteria has been identified the patient can be prescribed the appropiate antibiotic. Another reason why is so important to identify bacteria and to know its characteristics, is for pharmaceutical companies to come up with medication and to decided the type of vaccines that can be used to counter it.
Bacterium are microorganisms with an extreme importance in the world. Besides the fact that bacteria could have harmful effects, such as food spoilage and causing diseases in both human and animals, it could be exceptionally beneficial also. Bacteria has helped with the advancement of
Identification of bacteria is important for a verity of reasons, determining if a bacteria is normal flora, or potentially pathogenic as well as determining the bacterial source of an infection or outbreak. Identifying the bacteria is crucial when treating a bacterial infection because the correct antimicrobial or antibiotic must be used to successfully eliminate the infection and this cannot be done without the identity of the bacteria. Selecting the correct antibiotic is critical when dealing with an infection since not all antibiotics are equally effective against bacteria. Finding the identity of the bacteria causing the infection allows the doctor to prescribe the appropriate antibiotic. Unfortunately looking at only cell or colony morphology cannot lead to a conclusive result because there are many similarities in colony and cell morphology even among the eight bacteria used in this experiment.
Bacillus cereus is a gram positive, aerobic, motile bacterium commonly found in soil and food. Some of its strains are harmful to humans and cause foodborne illness, while other strains are beneficial as probiotics for animals. It can cause fried rice syndrome.
Day One: On the first day of our Biochemical Unknown Lab we were given a tube that contained broth media which held two different types of bacterium. Once we were given our broths, we had to streak two Nutrient Agar plates with the mixed culture tube by using a loop. After I streaked my Nutrient Agar plates, I decided to perform a gram stain. First I flamed the loop and set it aside to cool. After I flamed the loop I prepared two slides with a drop of water in the middle. Once the loop was cool I dipped the loop into the broth and smeared the loop onto both slides mixing the unknown bacterium with the water. I flamed my loop, set it aside, heat fixed both slides, and let the slides air dry. Once the slide were dry I set them on two rods above the drainage area and covered the smears with Crystal Violet. I let the Crystal Violet sit on the smear for one minute and rinsed off the Crystal Violet. Once the Crystal Violet was rinsed I applied Grams Iodine and let that sit for one minute. After one minute passed I rinsed the slide again and moved on to applying the alcohol. I dripped the alcohol onto the slide until the
Identifying bacteria is beneficial for several reasons. In the food industry, the discovery of bacteria and other microorganisms helped develop processes to prevent food spoilage, such as pasteurization, and bacteria is used to make certain foods, such as cheese, butter, vinegar, and alcohol (1). The discovery of bacteria that break down waste products is beneficial to the waste treatment industry, and the discovery of nitrifying, ammonifying, and nitrogen-fixating bacteria are important for growing crops in the agricultural industry (1). Bacteria and other microorganisms that can produce antibiotics have saved countless lives since the first antibiotic, penicillin, was discovered by Alexander Fleming (1). One of the most important
The purpose of this exercise was to isolate an unknown microbe and try to correctly identify its genus if not species using a variety of physical and chemical tests.
It is fascinating to look around and see how much diversity exists on earth. Perhaps even more interesting is the diversity that exists far beyond the naked eye. Over the past several decades, it has been determined that microorganisms account for the majority of the biomass on earth and new discoveries about these organisms are constantly being made (4). Bacteria make up a very large domain of the prokaryotes, or single-celled organisms. Bacteria have an enormous range of properties. Some can be infectious and lead to maladies and fatalities; others can benefit us by contributing to medications, foods, and even maintaining natural body functions like those in the digestive tract. Bacteria are virtually everywhere. It is for these reasons that it is vital we learn as much as possible about the once unseen organisms. Studying their physical and biochemical features can help us understand how to
Bacteria are unicellular microorganisms too small to see with the naked eye that exist in virtually all environments in the world. They inhabit various environments such as dirt, water, and inside the human body (Bacteria, What, 2015). These organisms that have the capacity to live as either independent organisms or parasites (MedicineNet.com, 2012) are remarkably powerful and complex in nature as they can be both vital and detrimental to the health of an organism. As some bacteria are pathogenic, they can be harmful to the body causing diarrhoea, urinary tract infections, respiratory illness and pneumonia, and other illnesses. An example of a bacteria capable of harming the human body to such extent is Escherichia coli
Microbiologist often times identify unknown microbes. When they are identifying microbes such as bacteria, a variety of tests are conducted to help determine different characteristics of the bacteria. By knowing the bacterial characteristics, they can eliminate and narrow down the possible genus of the unknown bacteria. The purpose of this paper is to identify the unknown bacteria in the test tube #53 by performing different tests. Aseptic technique was used throughout these tests in order to ensure proper results and to avoid contamination. Aseptic technique is used to transfer microbes from a pure culture to a sterile medium without contamination of oneself, others, the environment, the source of culture, or the