Pglo Lab

After 5 days the plates were removed from the cold room and the gram-negative test for Colony A on the EMB agar showed pink fisheye colonies which lead to the conclusion that the gram-negative organism within Unknown #21 was Enterobacter aerogenes. Had the pigmentation been metallic green, the organism would have been identified as Escherichia coli, and had there been no pigmentation at all a Triple Sugar Iron agar (TSI) test among other tests would have been

The hypothesis for this experiment was that transformed bacterial cells would grow on ampicillin plates and glow green when exposed to UV light. The rationale for this hypothesis was because the plasmid would code for ampicillin resistance and a green fluorescent protein, we would have the outcome explained in the hypothesis. 4. Our predictions were that for the standard protocol plates with agar and ampicillin, there would be growth and the colonies would glow under UV light. On the modified protocol on plates with agar and ampicillin where we changed the time of the heat shock, we expected less growth but the colonies would still glow.

The Mut section is expected to have no growth as mutants require the amino acids leucine and valine to grow which is not provided in the minimal medium. Results Figure 2. Testing of mutant mixed with DNA, mutant bacteria and DNA on LB medium Growth was observed on the Transformed (Trsf) section and the Mutant (Mut) section but not on the DNA section. Due to human errors, the photo of our experiment was lost, but we have obtained similar results as from group1.1 and their photo is presented.

Q1A: What is the mechanism of action of colistin? Colistin is an antibiotic that works best against Gram-negative bacteria. It works by binding to LPSs (lipopolysaccrides) and phospholipids in the outer cell membrane of the bacteria. This, in turn, disrupts the outer cell membrane by displacing cations and leaking the intracellular contents, combining it with outer cellular contents, causing the bacteria to be unable to differentiate the bacteria’s intra and outer cellular contents from one another.

In the laboratory, identification of an unknown bacterium is often necessary. In the lab, a random sample consisting of three different bacteria was selected. The sample contained one gram-positive, one gram-negative paracolon, and one gram-negative coliform. The purpose of the experiment is to identify each of the three species that the mixture contained. After receiving an unknown mixture, the sample was streaked for isolation onto TSA, blood agar, and MacConkey plates.

The putrid smell of Escherichia coli is one that is immediately identifiable to the few lucky individuals who recognize its scent. It is also an aroma with which I became intimately sensitive to as I shuttled petri dishes of the bacterium in and out of an incubator. While my classmates shied away from the task of handling the pungent bacteria used in our recombinant DNA experiments, I took to the task eagerly, anything that would take me one step closer to my goal of researching. I had the opportunity to learn about lab techniques and cutting edge biology concepts the summer before my junior year, in an extracurricular biotechnology class at Northwestern University’s Center for Talent Development. The class, a three week crash course in the

E.coli strains that had SAT value ≤ 1.25 M were considered

The purpose of this experiment was to insert the plasmid glow green into the bacteria with a gene of interest to produce the protein that make the bacteria glow green along with the presence of arabinose and the presence of ampicillin. Many scientists are experimenting different kind of genes that can inserted into the organism for survival. The technique of transformation was used in this experiment to give the organism a new trait that they did not possess in their life. In this experiment, the bacteria were added to four plates with certain conditions such as the existence of plasmid, ampicillin, and arabinose to see whether the bacteria grow and glow green. The results showed that the LB/amp/araC +pGLO produce a lot of colony and most

Exercise 14: Unknown Identification Lab Report The purpose of the study was to identify the unknown bacterium using various biochemical tests in addition to using scientific methods in determining the outcome of the hypothesis. Each biochemical test will help determine the bacteria based on specific characteristics of each organism. I was giving unknown number 232. The first procedure that needed to be done after obtaining unknown bacterial mixture was to isolate the two bacteria in a pure culture using the streak plate method described in Microbiology Laboratory Manual Eight Edition. The material used was trypticase soy agar (TSA) plate, nutrient plate, starch agar, hydrogen peroxide, iodine reagent and microscope.

This explains why in the plate with ampicillin but no pGLO plasmid, the bacteria was unable to grow. If the pGLO plasmid did not contain ampicillin resistance, E.coli would not have been able to grow in the agar plates, rendering the experiment pointless. Secondly, the results exhibited the fact that arabinose allowed certain colonies in the E.coli bacteria to glow under UV light. Essentially, the arabinose acted as an inducer that binded to the repressor in the inducible operon, allowing the RNA polymerase to transcribe the DNA and synthesize the GFP, causing the bacteria to grow. In this case, the plasmid itself is not fluorescent because it is a gene and genes in DNA cannot glow themselves.

Although there are limits to these findings as it is impossible to say if the altered microbiota is the cause of the disease (Phillips,

After 48 hours, I observed different growth patterns around the disks. I measured the zone of inhibition of each antibiotic and document them on Microbiology task 3

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

Contrary to popular belief, Charles Darwin was actually not the first biologist to suggest that species rehabilitated over time into new more developed and advanced species. Darwin alongside Jean-Baptiste Lamarck and a few other naturalists eventually coined the concept of evolution by the end of the 1700s. For most of his life, Lamarck focused on his two proposed mechanisms, of which both were very successful in the science world. As species adapted to the environment and their surroundings, the nature of their species also began to progressively adapt and become more complex springing from simple to more complex beings. Lamarck also hypothesized the idea of spontaneous generations in which he theorized that new primeval life species essentially

Nasty strains like E-coli 0157:H7 can resists heat up to 44°C and also resists drying and