In today's medicine, correctly and quickly identifying a patient's illness is essential for proper treatment. In order to execute this, biochemical tests of various magnitudes are used to identify what a patient may be infected with. In our lab, we received an unknown sample of urine. After several biochemical tests, we determined our unknown specimen to be Enterobacter aerogenes.
This particular bacterium is gram-negative, with rod shaped morphology. In order to determine whether our specimen was gram-positive or negative, we conducted a gram stain. After analyzing the resulting dyed smear on the slide, pink, rod-shaped bacteria were prominent. We next created a streak plate in order to grow our particular specimen and isolate colonies from it. Our streak plate was grown on MacConkey agar, which is used to differentiate between lactose fermenters from non-lactose fermenters. It also selects for
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gram negative bacteria. If the bacteria are gram positive, no growth will occur due to the bile salts and crystal violet present in the agar. A neutral pH indicator is used in order to grow the bacteria. If the bacteria are a lactose fermenter, it will produce a red halo around the area inoculated. A non-lactose fermenter will be yield colorless colonies. We next conducted a Lactose Carbohydrate Test. This particular biochemical test is used to determine if the microorganism is able to ferment a specific carbohydrate, glucose. In each of the tubes, gas was produced in the Durham tube along with a yellow broth coloration. A positive result was recorded, indicating the bacteria was able to break down the glucose, using anaerobic fermentation. The second test we conducted was the Dextrose Carbohydrate Test. This particular test aimed to determine if our unknown was able to break down dextrose. A positive result was found, indicating the presence of dextrose. The next test we conducted was with an Eosin Methylene Blue (EMB) agar. This particular agar is selective for gram negative bacteria (called enterobacteriaceae). It also differentiates between lactose fermenters and non-lactose fermenters, similarity to MacConkey agar. After incubation, thick purple convex colonies grew, indicating it was a lactose fermenter. A non-lactose fermenter would have generated colorless colonies. The last test we conducted was a urinary-tract-infection (UTI) test on HardyCHROM agar. After incubation, dark blue, colonies resulted, indicating the growth of Enterobacter colonies, specifically the species aerogenes. In order to further determine our unknown specimen, we conducted three additional biochemical tests. The first test we performed was a Lipid Hydrolysis test, which tests a the presence of lipase, which breaks down lipids into glycerol and fatty acids. After incubation, no zone of clearing resulted around our culture. This was indicative of a negative result for lipid hydrolysis. The second test we conducted was a Gelatin Hydrolysis test, which tests for an organism's ability to break down gelatin by gelatinase. Gelatinase allows gelatin to keep a liquid composition four degrees and higher. Gelatin, is solid below 25 degrees Celsius and liquid above 25 degrees Celsius. We inoculated our unknown organism in the gelatin tube. After 30 minutes, we placed it in the refrigerator at 37 degrees Celsius. After seven days, the gelatin remained a liquid, indicating slow gelatin hydrolysis. This is indicative of a negative result. The third test we completed was a Urease test, which tests for the presence of urease in a culture. Urease, an enzyme, is responsible for catalyzing the hydrolysis of urea into by-products, carbon dioxide and ammonia. Since ammonia is an alkaline end product, it turns bright pink when exposed to a pH indicator called phenol red. This color change from orange to a bright pink color indicates the presence of urease, a positive test result. The final test we conducted was a urinary-track-infection (UTI) test on HardyCHROM agar. Convex colonies, with a deep indigo color resulted. We compared them to known samples, indicating our unknown was Enterobacter aerogenes. Enterobacter aerogenes, an opportunistic pathogen, is responsible for causing infections in immunocompromised individuals.
It is commonly found in the human gastrointestinal tract, soil, wastes, and often hygienic chemicals ("Enterobacter Aerogenes"). It often found on stainless steel or copper surfaces in great quantities. Therefore, making sure all appliances and equipment in hospitals are sterile in order to decrease possibility of nosocomial infections. Common equipment found contaminated with the bacteria are parenteral nutrition solutions, digital thermometers intravenous catheters, mechanical ventilators, and dialysis equipment (Jha 2016). Enterobacter aerogenes is primarily known to cause skin and eye infections. It also can cause urinary-tract-infections and lower-respiratory infections. Individual who remain in the hospital for extensive periods and the dialysis unit are most prone to acquiring an infection from enterobacter aerogenes (Jha 2016) As a result, proper personal protection (PPI) equipment and hand washing around those who are infected is
essential. Several different antibiotics including carbapenemes are best known to treat against enterobacter aerogenes and other enterobacter species. Bectalactams, fluoroquinolones, aminoglysodies, and TMP-SMZ are all common treatments (McGrath 2017). Enterobacter aerogenes are also known to be resistant to ampicillin, sulbactam and imipenem (Jha 2016) Enterobacter aerogenes isn't one of the most dangerous bacteria's known if contaminated with, but is very contagious. It overall has a low mortality rate, around 10 percent (McGrath 2017). In rare cases, enterobacter aerogenes can enter an individual's cerebrospinal fluid and can cause meningitis.
The unknown bacterium that was handed out by the professor labeled “E19” was an irregular and raised shaped bacteria with a smooth texture and it had a white creamy color. The slant growth pattern was filiform and there was a turbid growth in the broth. After all the tests were complete and the results were compared the unknown bacterium was defined as Shigella sonnei. The results that narrowed it down the most were the gram stain, the lactose fermentation test, the citrate utilization test and the indole test. The results for each of the tests performed are listed in Table 1.1 below.
After 48 hours of incubation the agar plates were viewed. Individual colonies were tested for successful isolation by gram staining and then viewing the stained bacteria under a microscope. Isolation was successful. One colony of each unknown bacteria was transferred to an agar slant for growth. The agar slants were stored at room temperature over the weekend so that they would not grow too much.
Living organisms undergo chemical reactions with the help of unique proteins known as enzymes. Enzymes significantly assist in these processes by accelerating the rate of reaction in order to maintain life in the organism. Without enzymes, an organism would not be able to survive as long, because its chemical reactions would be too slow to prolong life. The properties and functions of enzymes during chemical reactions can help analyze the activity of the specific enzyme catalase, which can be found in bovine liver and yeast. Our hypothesis regarding enzyme activity is that the aspects of biology and environmental factors contribute to the different enzyme activities between bovine liver and yeast.
The purpose of this study is to identify an unknown bacterium from a mixed culture, by conducting different biochemical tests. Bacteria are an integral part of our ecosystem. They can be found anywhere and identifying them becomes crucial to understanding their characteristics and their effects on other living things, especially humans. Biochemical testing helps us identify the microorganism present with great accuracy. The tests used in this experiment are rudimentary but are fundamental starting points for tests used in medical labs and helps students attain a better understanding of how tests are conducted in a real lab setting. The first step in this process is to use gram-staining technique to narrow down the unknown bacteria into one of the two big domains; gram-negative and gram-positive. Once the gram type is identified, biochemical tests are conducted to narrow down the specific bacterial species. These biochemical tests are process of elimination that relies on the bacteria’s ability to breakdown certain kinds of food sources, their respiratory abilities and other biochemical conditions found in nature.
One of the most primitive actions known is the consumption of lactose, (milk), from the mother after birth. Mammals have an innate predisposition towards this consumption, as it is their main source of energy. Most mammals lose the ability to digest lactose shortly after their birth. The ability to digest lactose is determined by the presence of an enzyme called lactase, which is found in the lining of the small intestine. An enzyme is a small molecule or group of molecules that act as a catalyst (catalyst being defined as a molecule that binds to the original reactant and lowers the amount of energy needed to break apart the original molecule to obtain energy) in breaking apart the lactose molecule. In mammals, the lactase enzyme is present
Enterococcus faecalis is a genus of gram positive cocci and form short chains or are arranged in pairs. They are nonmotile, facultative anaerobic organisms and can survive in harsh conditions in nature. There are over 15 species of the Enterococcus genus but about 90% of clinical isolates are E. faecalis. E. faecalis is a nosocomial pathogen because it is commonly found in the hospital environment and can cause life-threatening infections in humans. It is a bacterium that normally inhabits the intestinal tract in humans and animals but when found in other body locations it can cause serious infections. The most common sites for E. faecalis infections are the heart, bloodstream, urinary tract, and skin wounds. Due to vancomycin-resistant Enterococci, many antibiotics have been shown ineffective in the treatment. In this paper, I will describe the ecology and pathology of E. faecalis; the antibacterial resistance; treatment; and, what you can do to prevent Enterococcus infection.
The purpose of this project was to identify unknown bacteria species from a mixed culture. The two unknown species were initially plated onto Tryptic Soy Agar (TSA), Eosin Methylene Blue (EMB), Mannitol Salt Agar (MSA), and blood agar plates to distinguish between the two different bacteria using colony size, color, shape, and growth characteristics. By identifying and inoculating the differing types of colonies, the two unknown bacteria were purified and able to be tested
Planaria are one of many free-living flat worms that can be found in marine, aquatic, and terrestrial environments. Certain characteristics of planaria worms include an acoelomate body, a gut with no anus, lack of a blood vascular system, and a simple nervous system. The main reason as to why planaria are subjected to many studies is because of their unique ability to regenerate. Regeneration is the ability to re-grow lost body parts that may have been cut off. This is possible because the organism has the ability to form a blastema, which is an accumulation of undifferentiated cells, at the site of the wound. Regeneration is capable of occurring at various degrees throughout the animal kingdom. This unique process would never be able to be seen in human beings. Humans and other mammals
This line graph shows how some phenotypes were more successful than others. This is an accurate representation of natural selection. The dark blue, pink, and orange phenotypes became extinct before the experiment was even finished. The successful phenotypes were green, purple, and yellow.
LAB REPORT 1st Experiment done in class Introduction: Agarose gel electrophoresis separates molecules by their size, shape, and charge. Biomolecules such as DNA, RNA and proteins, are some examples. Buffered samples such as glycerol and glucose are loaded into a gel. An electrical current is placed across the gel.
The background of a gram negative will show layers of the cell wall that hold layers that are peptidoglycan and it also shows that this bacteria has an outer layer that is asymmetrical bilayer (Oliver,2017, p. 33-34). The gram negative rod appeared pink with a thin-long stretched out circular shape. This appeared on the slide once the correct magnitude was place and oil was added. From the results of the gram stain, many of the bacteria were crossed of the chart and it only left two microbes. These two organisms which were Escherichia coli and Enterobacter aerogenes made it difficult to choose from because some of the test matched for both organisms. From the start, it was a difficult choice at first. The result seemed that it could have been E.aerogenes, but with studying the results the choice of E.coli fit all the results more than the first
Nursing diagnosis Hospital acquired infections are spread by numerous routes including contact, intravenous routes, air, water, oral routes, and through surgery. The most common types of infections in hospitals include urinary tract infections (32%), surgical site infections (22%), pneumonia (15%), and bloodstream infections (14%). a. (book). The most common microorganisms associated with the types of infections are Esherichila coli, Enterococcus species, Staphylococcus auerus, Coagulase-negative staphylococci, or Pseudomonas aeruginosa. Urinary tract infections occur when one or more microorganisms enter the urinary system and affect the bladder and/or the kidneys.
Farmers around the world may not be able to afford fertilizers because of high cost. Anyone that has recently visited a nursery can verify how expensive chemical and organic fertilizers have become. However, there is another plentiful and inexpensive fertilizer alternative: human urine. Human urine contains very few, if any pathogens. However, it contains the majority of plant fertilizing nutrients. Human urine contains high levels of nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), calcium (Ca), and sulfur (S). An additional benefit of using human urine, is that you are collecting it instead of flushing it, saving gallons and gallons of water.
Thomas J. Sandora and Donald A. Goldmann (2012) believe that basic infection control procedures are the way to decrease and stop antibiotic resistant bacteria strains from spreading and developing. Proper handwashing is one way to reduce the transmission and creation of new antibiotic resistant bacteria in the healthcare setting, “MDROs are transmitted mainly on the hands of caregivers who do not practice effective hand hygiene after every contact with patients and their environment” (p. 2168). Wet, lather, scrub, rinse, and dry must be done for at least 20 seconds with warm water and soap in order to be effective in the prevention against antibiotic resistant bacteria. Patients in a hospital are already immunocompromised, so acquiring a MDRO increases the chance of fatality. Sandora et al.
The Cell, the fundamental structural unit of all living organisms. Some cells are complete organisms, such as the unicellular bacteria and protozoa, others, such as nerve, liver, and muscle cells, are specialized components of multicellular organisms. In another words, without cells we wouldn’t be able to live or function correctly. There are Animal Cells and Plant Cells. In Biology class the other day we studied the Animal Cell. We were split into groups of our own and we each picked a different animal cell slide to observe. My group chose the slide,'; Smeared Frog Blood ';.