After a gram stain was done unknown #257 was identified as a gram positive organism because when observed under the microscope the organism appeared purple with cocci in clusters. The organism was also catalase positive which means that it produced enzyme catalase and bubbled when hydrogen peroxide was added to it.
Three test were conducted based on the result of the gram staining procedure. Blood agar with a Novobiocin disk was chosen as well as DNase (DNA) and Mannitol Salts (MSA) agar. The Blood agar is a bright red, opaque plate and the streaking or the inoculation technique was a modified streaking for isolation with a heavy quadrant one. This is where the antibacterial disc bacitracin was used to determine the bacteria’s susceptibility.
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The streaking technique used was a modified streaking for isolation with a heavy quadrant one. The result revealed that bacteria is alpha, with an incomplete breakdown of the medium with a susceptibility of 17mm from the bacitracin gamma hemolysis. That is why the organism represented by the bar graph was in low numbers because it was incomplete. The other test was DNase agar, it is an enzyme test used to identify if the organism has the enzyme DNA. The streaking technique is a single straight line down the middle of the plate. The unknown #257 tested positive for the enzyme DNase. Lastly, Mannitol Salt Agar (MSA) was used to test for isolation and differentiation. The streaking technique used is streaking for isolation.The unknown #257 tested positive for mannitol fermentation which means the organism is …show more content…
SIM tube was used as well as the Triple Sugar Iron (TSI), MacConkey agar (MAC) and Citrate Slant. The SIM tube is used to identify hydrogen sulfide production, indole, which is a by-product of tryptophan which is broken down by tryptophanase and motility. The streaking technique used is a half stab. The TSI has an orange color and it used to identify carbohydrate fermentation specifically glucose, lactose, and sucrose fermentation. The TSI is used to observe the slant and butt of the tube as well as to identify if gas was present and if the organism produced hydrogen sulfide. The Another medium used was MAC, it is used to isolate and differentiate gram-negative organisms and it is a pink, dusty rose color. Lastly, the Citrate Slant is a green color and it was used as a differential test to examine enzymes. The media were inoculated at 37°C for 48 hours, then it was observed to determine the
The plate labeled LB/amp/ara: +pGlo had several surviving colonies like the other +pGlo plate, except this time the colonies were a green color and the glowed under a UV light. The glow would be a result of adding the sugar arabinose, which seems to be acting as an inducer in the operon of the bacterium. It can be considered an inducer because in the presence of the arabinose, the colonies glowed, but without it the colonies did not experience any change, leading to the belief that the gene that leads to the green fluorescence is normally turned off. To further the research on the effect of the arabinose on the E. coli, a sample of the bacteria in the LB/amp: +pGlo and placed it in a plate with arabinose lines across the bottom.
Staphylococcus epidermidis is the organism that was identified based on the tests that I had conducted. The tests that I used to identify this organism were the coagulase test and the catalase test. My bacterium was beta hemolytic as well. First, a gram stain had to be done to determine whether the organism was a gram positive organism or a gram negative organism. This determined which set of tests that had to be done.
Starch solution is then placed into the test tube at a quantity of 5 mL. 5 drops of Lugol’s Iodine solution is added to the test tube. If the color changes, then it is known that starches are present in the solution. Proteins are next tested. In order to do this, 5 mL of gelatin solution is added to the test tube. 10 drops of Biuret’s reagent are added to test for protein.
The investigation was carried out to identify the presence or absence of biological molecules in serum 2216. If the concentration in each test tube of the dilutions carried out will be more concentrated then the concentration of the test tube before it, then the color will be at an equal concentration with the other dilutions performed. The hypothesis was wrong because of the difference in concentrations due to the different measurements within the dilutions done. The test for starch was to add a drop of iodine solution to the pipette in the spotting tile. A reducing sugar solutions is add inside a test tube with 3 drops to then add 3 drops of benedicts and plane in a water bath.
According to the series of test that my group ran for our unknown specimen, we had a match with the bacteria known as Alcaligenes Faecalis. This bacterium belongs to one of the major group of gram-negative bacteria (Phylum Proteobacteria). Alcaligenes Faecalis (Genus, species) is a rod shaped (bacillus), 0.5-1.2 x 1.0-3.0 µm, round with scalloped margin (colony configuration growth), motile (with one to nine peritrichous flagella), gram-negative, non-fermentative bacteria, obligate aerobic, having oxygen as the principal terminal electron acceptor in the electron transport chain (ETC). We consider we have a match with the species Alcaligenes Faecalis because of the following reasons: Fermentation tests performed (Durham sugars) were negative, which indicate that our bacteria use a different metabolic means for growth (non-fermentative gram-negative bacteria).
The sterile cotton swab was inserted in the S. epidermidis culture and twirled around to obtain a specimen. The entire plate was inoculate with the swab from top to bottom, to achieve a lawn of growth. The dry forceps was used to remove the antibiotic disk into the appropriate spot on the plate. This process was repeated for the all antibiotics with aseptic technique being used. The plate was incubate with lid up on the bookshelf at room temperature for 48 hours.
Uncontrolled Environmental conditions Atmospheric conditions The controlled variable Concentration of amylase was kept under control by measuring the amount of amylase used and also it was made sure the percentage of amylase used was 1%. The Amount of amylase/starch used were kept to 5cm3 at all times. Materials needed Beakers Bunsen burner Test tube Thermometer Stopwatch Test plate Glass rod Starch Amylase solution Water bath Iodine solution. Test tube holder Labels Marker Procedure First 5 test tubes were taken and labeled with numbers from 1 to
Positive results should be red-purple residue. The principles involved in this test were oxidation of purine by concentrated HNO3; condensation reaction of alloxan to form alloxanthin; and neutralization which forms the red purple murexide or the potassium salt of purpurate. In the sample, the red-purple residue did not appear which means that there is the absence of purines in the DNA
After experiment on microscope under oil immersion, I learned that my Unknown is gram positive. Under the lens, the bacteria appears in purple color. Its morphology is cocci arranged in cluster. However, during decolorizing process, I put too much alcohol to the crystal violet-iodine complex making the color overly removed. That led to the result of my gram positive has slightly redish
Joshua Miller 12/18/17 Fermentation Lab report Introduction The term fermentation refers to the chemical breakdown of a substance by bacteria, yeasts, or other microorganisms, typically involving effervescence and the giving off of heat (wikipedia). Sugars are converted to ethyl alcohol when fermentation happens. In this experiment we determined if yeast cells undergo fermentation when placed in a closed flask with no oxygen. Glucose and yeast are mixed together in a closed flask and allowed to incubate for about one hour.
Finally, the amplified DNA regions are compare using a gel. DNA Profiling
INTRODUCTION: Arginase is an enzyme- enzymes are biological catalyst which drives a reaction at the speed of life. Arginase is a hydrolase, hydrolases catalyze hydrolysis reactions, this is determined via the E.C number (Nelson and Cox 2008). Arginase has the EC number is 3.5.3.1 (Schomburg 2015). The enzyme ‘commission number’ is the arithmetical classification that is used for enzymes which indicates the chemical reaction they catalyze.
Approximately 60-90% of the Gram-positive bacterial cell wall is made up of peptidoglycan and interwoven teichoic acid, while only
This can be tested by simply mixing the serum of suspected individual which contain the antibodies with the antigens of specific bacteria the accumulation of clumps confirms the presence of particular bacterial infection.[2] This test can be performed in various ways including slide agglutination reaction, tube agglutination reaction, indirect agglutination inhibition reactions etc. Another important practical application involves blood group test of
If the broth turned a reddish color, the result was then positive. If there was no color change, then a small amount of zinc powder was added. If there was no color change, the result was also positive, but if there was a red coloration development after the zinc was added, the result was then negative. Both Unknown bacteria (16A and 16B) were positive for nitrate reduction. The tubes were then