Unknown Bacteria Essay

The first result of importance was the result of the Gram stain. The observations of the unknown bacteria from the slant culture after Gram staining showed that the unknown bacteria were Gram negative bacilli (Image 1). After determining the unknown bacteria was Gram negative, an oxidase test was conducted on a sample from the slant culture. The cotton swap with the sample of bacteria did not change color when the oxidase reagent was applied, thus providing a negative result. With a negative oxidase test, further tests were conducted to determine various characteristics of the unknown bacteria. A MR-VP broth was inoculated with a sample from a slant culture of unknown bacteria. After incubation, the methyl red reagent was added to the broth, and the broth turned red, providing a positive result (Image 2). An EMB agar streak plate was inoculated with a sample from a slant culture of the unknown bacteria, and after incubation, growth was found on the plate, providing a positive result (Image 3). A Citrate agar slant was inoculated, and after incubation, growth was found on the media, providing a positive result (Image 4). A Urea agar slant was inoculated, and after incubation, the agar had changed from a peach color to a bright pink color, providing a positive result (Image 5). Using the flowchart (Figure 1) developed from the Table of Expected Results, the lab partners started at the oxidase test. Given the negative result of the oxidase test, the flowchart is

In a laboratory setting, it often becomes necessary to identify an unknown organism. In this experiment, researchers classified an unidentified bacterium based on its physical structure, colony morphology, optimal conditions and metabolic properties. A Gram stain using crystal violet, iodine, and safranin and a simple stain using methylene blue characterized the organism’s cell wall. Cultural behavior was classified by inoculating the organism onto nutrient agar and incubating it at 37° C for 48 hours, and observing its behavior, as well as using SIM medium to test for motility. Optimal growth temperature was

The purpose of this lab was to identify two unknown bacteria cultures using various differential tests. The identification of these unknown cultures was accomplished by separating and differentiating possible

|MSA Agar |For organisms that are |Isolates for mannitol fermentation |Yellow color change in |Staphylococcus aureus |

This experiment was conducted to find the genus and species of an unknown bacteria prescribed by the lab teacher, which was unknown bacteria GA3 in my case. Identification of unknown bacteria techniques are used on an every day basis to figure out what type of bacteria it is and to find the best method of how to treat a patient with this bacteria (1). All five “I’s” of Microbiology were used in the testing for the unknown culture. Inoculation was used several times to put the unknown culture into agar plates or into biochemical test tubes. After Inoculation of these tubes or plates, they always were placed into the incubator for further growth and development. Isolation was used to make sure we got the correct bacteria we were testing for. After each further isolation, we gram stained the culture and inspected the culture under a microscope to further help in the identification process of the unknown bacteria. Multiple tests were done on the unknown culture to make sure we were confident in what kind of bacteria the unknown was.

Microorganisms are both beneficial and harmful. These microorganisms are important to humans because they play a role in the ecology of life, by decomposing wastes, both natural and man-made, such as creating nitrogen fertilizer at the root zones of certain crops. Other several pathogens that can cause serious harm, even immediate death due to the diseases or disease causing products they produce. Overall, microorganisms play an important role in life.

Mannitol Salt Agar contains the carbohydrate mannitol, 7.5% sodium chloride (NaCl), and a pH indicator called phenol red. At pH levels below 6.9, the medium is a yellow color. In the neutral pH ranges (6.9 to 8.4) the color is red; while above pH 8.4, the color of phenol red is pink (Gerhardt P., 2011). Acid is produced when mannitol is fermented by bacteria, which lowers the pH and results in the formation of a yellow halo surrounding the isolated colony on MSA. Non-fermenting bacteria that withstand high salt concentrations will display a red to pink area due to peptone breakdown (Mahon C.R. et al.

The species ID from the Biolog was confirmed to be Staphylococcus epidermidis with a probability of 99.2%. The observed results of utilization of D-Mannitol, citric acid, D-fructose, and α -D-lactose matched the expected results. The bacteria sensitivity to NaCl differ from the expected results; the bacteria should be tolerant to NaCl up to 10-15%. The fermentation results of glucose and lactose from phenol red broth was different from the results observed in the Biolog. The Biolog results matched the expected results for S. epidermidis with a few exceptions. From the citrate slant test, it was observed that the bacteria was unable to utilize citrate; however, the observed results from the Biolog test was inconclusive indicting a positive and negative result. The bacteria was indicated to not be sensitive to Vancomycin, however, the bacteria is expected to be sensitive to the antimicrobial

The sole purpose of this project was to identify an unknown bacteria sample #7. Many tests were carried out to determine what this unknown was. Aside from a microbiology lab, understanding and identifying various organisms are important in disease processes, pharmaceutical arenas, and even in the industrial field. Proper lab techniques, including aseptic technique were used throughout the process of identification.

In the world of microbiology it is vitally important to be able to discern the identities of microorganisms. Not only is it important in a lab setting but as well as in healthcare in general. Properly identify what strain of bacteria a person has will aid in the proper medicine and dose given. Throughout the semester we have learned about different types of bacteria and certain test that can clearly identify them. The purpose of this lab report is to identify a Gram-positive or Gram-negative bacterium. Using all the knowledge of procedures and lab techniques identify the unknown and discuss all the tests you performed.

Staphylococcus aureus is a gram positive cocci that forms grape like clusters, produces catalase, has a peptidoglycan and teichoic acid cell wall, and has a G + C content of DNA ranging from 30-40 mol%. An estimated 20% of the human population is long-term carriers of S. aureus, appearing in the nares of the nasal passages and also part of the natural skin flora which is the most common species of Staphylococcus to cause Staph infections. S. aureus is a successful pathogen due to a combination of nasal carriage and bacterial immuno-evasive strategies. S. aureus can cause minor skin infections, pimples, impetigo, boils or furuncles, cellulitis, folliculitis, carbuncles, scalded skin syndrome, and abscesses. Life-threatening diseases such as pneumonia, meningitis, osteomyelitis, endocarditis, toxic shock syndrome, bacteremia, and sepsis are also caused by pathenogenic S. aureus. Its extent ranges from skin, soft tissue, respiratory, bone, joint, and endovascular to wound infections. Nosocomial infections and often postsurgical wound infections are a commonly caused by S. aureus. S. aureus is also a prominent cause of food poisoning in the US, and can be transmitted by different foods, including milk and

MRSA is short for methicillin-resistant Staphylococcus aureus bacteria and can be potentially fatal due to the fact they are not responsive to main antibiotics. S. aureus is a bacterium and not a virus and the most pathogenic of the staphylococci. This infection is one of the first found to be resistant to strong antibiotics. Bacteria are unicellular microorganism, while a virus is a sub-microscopic particle that infects the cells of an organism causing serious skin infectious boils. This superbug is major health concern for the public. This paper will shed some light on the major symptoms MRSA presents, how it spreads, how to prevent it from spreading, and treatments.

What are the differences between bacterial, viral fungal and parasitic infections? How is each treated?

The release of two exotoxins from certain strains of S. aureus can lead to Staphylococcal scaled skin syndrome (SSSS), which is characterized by blistering skin. Invasion into the body can lead to more serious health problems including pneumonia (a frequent complication of influenza), mastitis, phlebitis (inflammation of the veins), meningitis, and urinary tract infections. If the bacterium is allowed to colonize even deeper tissues more serious conditions such as osteomyelitis and endocarditis may result. The most serious consequences of these deeper tissue infections occur when the bacterium invades the bloodstream leading to septic shock and possibly death.

2. Introduction: Each student was given unknown bacteria and was instructed to perform a variety of experimental tests that would help to identify their bacteria. During the process of identification, the unknown bacteria was added to many different testing medias using aseptic technique. They are as follows: lactose fermentation on eosin methylene blue (EMB), TSI (Triple Sugar Iron agar), Phenol red sucrose, the SIM test, H2S by SIM, IMViC (indole, motility, voges-proskauer, and citrate), Urease (urea broth), PDase (Phenylalanine Deaminase), Lysine Decarboxylase, and Ornithine Decarboxylase. Colonial morphology on EMB was used to