A Research Study On Enterococcus Faecalis

The first step to identifying the unknown bacteria residing on the blood agar plate sent in from Khokana was to do a Gram stain on it. This is an important first step because it dictates further testing that will be necessary to arrive at a final conclusive result. Viewing the fixed and stained slide under the microscope revealed round chains of bacteria in a purple color signaling Gram-positive streptococci. A catalase test was performed with no bubbling present indicating a negative result. This further confirmed the shape and arrangement seen under microscopy. With this mind, the coagulase test was not done, as it would be of no use since that specifies for staphylococcus, specifically for Staphylococcus aureus. For streptococcus, an examination of hemolysis was necessary at this point. Shifting attention back to the original blood agar plate, gamma hemolysis was noted, thus narrowing the field down to two choices left. The unknown bacteria was either Streptococcus bovis or Entercoccus faecalis. This also means the Optochin and Bacitracin sensitivity tests would not be needed as those pinpoint alpha- and

The first a catalase test uses hydrogen peroxide to see if it can be reduced to oxygen and water by the presence of bubbles. The next test, Bile Esculin, which is an Esculin medium that if the bacteria reacts with the ferric chloride the agar will turn black. The last test being used is a SIM test which is a few tests in one. It tests for sulfur reduction, which would turn black; motility, which shows growth around the incision and indole production, which is the removal of an amino group and its reaction with the Kovacs reagent turning a red color (Allen, 2016). The whole premise of this lab is to take an unknown sample and try and separate it into both Gram-positive and Gram-negative bacteria.

Bacteria are ubiquitous; they can be found on the skin, in the soil, and inside the body. Because of the very nature of this ubiquity, it is important to be able to determine between different strains of bacteria. An example of this is determining the causative agent for a disease so that the patient will be treated with the appropriate antibiotics. It may be important to determine the bacteria in a certain region, because like with enteric bacteria, it is normal to find them in the digestive tract as they are in a symbiotic relationship with our bodies in this area; however, they also cause opportunistic infections in places outside of the digestive tract to our detriment, such as with a urinary tract infection. Some strains of bacteria are common to nosocomial infections, and identifying these bacteria as such helps create the guidelines for healthcare workers in antiseptic technique. All of the morphology and characteristics of each strain of bacteria help us to better understand the role of bacteria in the body as well as helps us understand how they can cause illness, and what treatment regimen to set in place. In lab this semester, a sample of unknown

The gram stain test was able to identify the bacterium as a gram-positive organism, and the morphology distinguished it as a strain of streptococcus, and these finds helped direct the other tests. Hemolytic tests are very useful in differentiating specific species of a certain family of bacteria. The hemolytic test showed the bacterium to be of alpha clearing, which meant it only partially lysed the red blood cells and left a greenish tint. This identified the bacterium as either strep pneumoniae or faecalis. The bacitracin test, which tests whether the bacterium is susceptible to the antibiotics in the disk, posted a positive

Bacteria, single-cell microorganisms, are found all over the planet. Some can be beneficial to their enviroment, while others can be pathogenic. Enterococcus faecalis is a resilient bacterium that resides in the intestinal tract of humans and mammals. Due to their ability to colonize at a rapid rate, E. faecalis cause a multitude of infections. To determine an unknown bacteria, one gram stain and two biochemical tests, a catalase and RBC hemolysis test, were performed. The gram stain showed gram-positive cocci bacteria, which lead to the catalase test. The test for

The oxidation fermentation test was used to differentiate if the organism utilizes lactose, mannitol, glucose and citrate aerobically (oxidation) or anaerobically (fermentation). A methyl red test was performed to determine if the organism carried out mixed-acid fermentation when supplied glucose. A Voges-Proskauer test was performed to evaluate if the unknown was able to ferment glucose into butanediol. A citrate test was performed to determine if the unknown organism was able to break down citrate into ammonia. An oxidase test was then performed to determine if the unknown culture was oxidase positive or negate.

As the flowchart shows, a series of tests were conducted to identify the unknown bacterium #65. Microscopic observation of the gram stain indicated a gram-positive coccus bacterium. S. epidermidis was used as the gram-positive control while E. coli was used as the gram-negative control. This observation led to the elimination of all gram negative and rod-shaped genera: Enterobacter, Citrobacter, Klebsiella, Escherichia, Pseudomonas, Serratia, Alcaligenes, Neisseria, Proteus, Salmonella, Shigella, Erwinia, Veillonella, Flavobacterium, Bacillus, Arthrobacter, Lactobacillus, Listeria and Kurthia (2). By performing the catalase test, it was determined that the bacterium was catalase negative and it did not produce bubbles. M. luteus and E. faecalis were used as positive and negative controls, respectively.

The bases of this experiment was to discover the identify of the unknown from three possible specimens: Klebsiella pneumonia, Escherichia coli, and Enterobacter aerogenes. Utilizaing the T streak technique, the bacteria was isolated into pure colonies for further study. The Gram Stain method was used to identity the morhphology of the bacteria such as the shape and whether the bacteria was Gram positive or Gram negative. Biochemical test were also used to help identify the unknown bacteria. The biochemical test used was the Triple Sugar Iron Agar, Sulfur Indole Motility test, Methyl Red test, Voges-Proskauer test, Citrate test, Urease test, and the Gelatin test. After observing the morphology of the bacteria using the Gram Stain method and utilizing all the possible biochemical test, the bacteria was identified to be Enterobacter aerogenes.

Once observing the bacteria with the microscope at the highest magnification of 1000 oil immersion each student should know if the unknown bacteria is gram positive or negative as well as if the microorganism morphology is coccus which is cells sphere shape or bacillus rod shape. If the microorganism is gram positive under the oil immersion should show purple, but if gram negative pink should show up. Proceeding to the catalase test by taking a slide and using a sterile loop put a small sample of bacteria on a clear glass slide then place a couple drops of the hydrogen peroxide on the bacteria. Afterwards students are able to choose which media would be best to get results to identify the unknown bacteria.

A great deal of cultural tests and physiological procedures were performed on the unknown before the conclusion of P. aeruginosa was made. The first test preformed was Gram’s staining which involves the use of crystal violet, Gram’s Iodine, Ethyl Alcohol, and Safranin. Gram staining is known as a differentiating stain, since it can determine the presence or absence of peptidoglycan in the cell wall. The unknown bacteria were Gram stain negative. After that the motility of the cell was tested using a hanging drop slide. The slide was examined, but the results were inconclusive due to the inability to make a clear distinction between motility and Brownian motion. This test was not

The genus Streptococcus is classified as a gram positive bacteria because of the spherical or ovoid cells that often arranged in pairs and the color it turns too after undergoing the gram staining technique. Unlike the catalase positive genus Staphylococcus, Streptococcus is catalase negative (Fox). Many Streptococcus bacteria are known to be facultative anaerobes, meaning they prefer to grow in places that have no oxygen but will adjust to places that contain some oxygen (Holt, et al.). On the contrary, there are a handful of Streptococcus bacteria that are considered to be obligate anaerobes, meaning they are strictly prohibited from being around oxygen because they are unable to live. Growing this type of bacteria includes specific factors

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

Hemolysis test was performed according to the method described by Guttmann and Ellar (2000). Overnight cultures of isolated Enterococcus durans and Enterococcus hirae were streaked on blood agar and incubated at 37°C for 24 h. Blood agar plates were examined for signs of hemolysis. Blood hemolysis test was performed in duplicates.

Enterococci are gram positive cocci that can occur singly, in pairs or as short chains. They are facultative anaerobes, possessing the ability to grow in the presence or absence of oxygen. Enterococci can withstand harsh environmental conditions. There are currently 23 enterococci species and they are divided into five groups based on their interaction with mannitol, sorbose and arginine 5 .E. faecalis can survive extreme challenges. Its pathogenicity ranges from life-threatening diseases in compromised individuals such as bacteremia, septicemia, endocarditis, and urinary tract infections to less severe conditions, such as infection of obturated root canals with chronic apical periodontitis.The persistence of E.faecalis might be due to the

Bacteroides fragilis constitute 1% to 2% of colon resident microbiota and achieving approximately 30% of the total of organism cultured from feces (1-3) . Members of genus Bacteroides are important opportunist anaerobic pathogen(4). In this genus Bacteroides fragilis due to its virulence factor such as, adhesions, hemagglutinin, polysaccharide capsule and fimberia is considered to be the most virulence pathogen(2, 5). This organism isolates from exteraintestinal monomicrobial and mixed infections such as diabetic foot infection, brain, lung, intera abdominal, Intera pelvic abscesses, surgical site infections and sepsis(6-9). As well as this organism cause toxin dependent diarrheal disease in human. This bowel disease is one of the most important causes of morbidity and