B Subtilis Experiment

Again, label 7 1.5ml tubes 0 thru 6. Place 15μl of each serially diluted extract into its corresponding labeled tube. Next add 465μl of media into each tube. Then 60μl of Alamar blue in each tube. Finally add an additional 60μl of cells (adjusted to 10,000 cells/20 μl). Vortex each tube for 5 seconds. Now, take 3 different samples 190μl samples of concentration 0 and put it in Wells A2, B2, and C2. Repeat this step again by taking 3 more different 190μl samples of concentration 1 and putting it in wells A3, B3, C3. It should be noted that it is important to vortex each 1.5μl tube again be-fore putting it into the 96 well plate. Contin-ue this same procedure consecutively for the re-maining concentrations.

70µL of competent E.coli are added to both test tubes; pUC18 and Lux (Alberte et al., 2012). Both test tubes are then tapped and placed back into the ice bath for 15 minutes. While waiting, another test tube is obtained, filled with 35µL of competent cells and labeled NP for no plasmid. A water bath is preheated to 37 degrees Celsius and all three labeled test tubes are inserted into the bath for five minutes (Alberte et al., 2012). Using a sterile pipet 300µL of nutrient broth are inserted into both the control and Lux test tubes and 150µL are inserted to the no plasmid test tube to increase bacterial growth. All three test tubes are then incubated at 37 degrees for 45 minutes. Six agar plates are obtained and labeled to correspond each test tube, three of the plates contain ampicillin. A pipet is used to remove 130µl from each test tube containing a plasmid and insert it into the corresponding agar plate. For this, a cell spreader is first

From there the bacterial colonies were transferred into a tube with CaCl2. 3ul of PBY006 were added into a centrifuge tube by using a pipette. The Centrifuge tube was then chilled on ice for 10 minutes. Once the ten minutes were up it was placed in a 42 degree C heat block for 50 seconds. After being chilled and heated 200 ul LB was added into the centrifuge tube.

The purpose of the following study is to determine where the two unknown bacteria acquired in Microbiology lab should be classified in regards to temperature, pH level, and osmoregularity. It is important to classify bacteria in order to identify them. Identification of bacteria is important because they are not only useful but potentially dangerous as well. The identification of bacteria can lead to breakthroughs in healthcare regarding treatment of old and new diseases alike. Identifying bacteria can also be used in many other areas from better crop production through microbial pesticides to biological warfare. Their uses are endless as are their abilities to evolve and adapt to changing environments. That is why it is so important

Then you add 100ul of PBS to each well, and then remove it. After that, to each well using different tip each time add 100ul PBS to number 1, add 100ul B to number 2, add 100ul C to number 3 and add 100ml D to number 4. Incubate at 37C (Body temp) for 15 mins. After that, remove liquid using different tips. Next add 100ul PBS, and then remove using different tips. Add 100ul 2C AB to each well and incubate at 37C for 15 min. remove the liquid using different tips, add PBS then remove the PBS. Add 100ul of substrate to each well and incubate at 37C for 5 mins.

Add 300uL of E.coli bacteria to the 10%, 1%, 0.1%, 0.01%, 0.001%, 0.0001%, and 0% bleach solutions. Vortex the solutions to mix well. After letting the mixture sit for 30 minutes, add 75uL of E.coli/bleach solution to each plate. Use glass beads to spread the bacteria evenly on the plate. Data/Results Figure 1

The optimum growth temperature of most species of bacteria is at body temperature, approximately 37 ᵒC, while some bacteria reproduce best at high temperatures 2. Some of the nutritional requirements are sources of carbon and nitrogen, water, minerals, vitamins, and organic and inorganic compounds3. When bacteria are grown in laboratories, culture media are sterilized and contain the substances required for the growth

3. Use a sterile pipette to transfer 0.1 ml of each dilution on to a MacConkey agar plate.

Next, using proper inoculation technique, which is heating the loop with a Bunsen burner until it is red hot and cooling it in the edge of the medium agar, grab a small but barely visible amount of Bacillus Cereus and drop it into the nutrient agar slant. Heating the tube in an 80-degree Celsius water bath should kill all of the vegetative bacterial cells in the sample, but the endospores within the sample should remain since they are resistant to heat. Once the sample has cooled, these endospores will be able to germinate to form vegetative cells. After cooling the beaker with the sample with ice, using proper inoculation techniques once again, use the 13- streak technique as used in Exercise 1.4 to streak the plate, then store the plate inverted at 37-degrees Celsius. The 13-streak technique is used isolate a bacterium into a pure culture from a mixed population [12].

Being able to control bacterial growth is something that is important in our everyday lives. As shown in the previous labs, bacteria can grow and create colonies extremely quickly especially in the right environments. By acknowledging this, it is then important to get an understanding of how bacterial growth can be controlled by humans. To control microorganisms it means to inhibit their growth (static) and or kill them (cidal) (Kenneth Todar, 2015); therefore since focusing on bacteria the terms bactericidal and bacteriostatic are both extremely important for this lab. One broad method we will use to control bacterial growth is heat. The amount of heat needed to control bacterial growth is different for different species of bacteria (Kenneth Todar, 2015). Bacteria can also respond differently depending if moist heating method such as an autoclave with steam is used, or a dry heating method such as inoculating a loop over a fire is used (Kenneth Todar, 2015). UV works by damaging the cells DNA, without proper DNA, the cells will die and the object

The purpose of the two experiments was to determine the fundamental effects that temperature has on the growth and survival of bacteria. During the first experiment five different bacterial broth cultures of Escherichia coli, Pseudomonas fluorescens, Enterococcus faecalis, Bacillus subtilis and Bacillus stearothermophilus were individually incubated at temperatures of 5, 25, 37, 45 and 55°C for one week in an aim to distinguish the effect temperature has on growth and survival of the five different species. After one week they were observed for distinguishable changes by the turbidity showing an indication of bacterial growth, or the clarity an indication of no survival.

1. Number four clean test tubes 1-4. 2. Place 1 ml (or 20 drops) of the following solutions into each tube: water, egg albumin, starch, and chicken broth. 3. Add 3 drops of Buiret reagent to each tube and gently shake

Add to this 5 drops of pH 4 buffer solution * Measure out 2 cm³ starch solution * Start stopclock and leave for 1 minute * Measure out 1 cm³ amylase and place in second corvette * Add to this 2 cm³ distilled water *

Microbial growth can be affected by different environmental factors such as temperature, osmotic pressure, oxygen concentration and pH. Six experiments were carried out in this report testing for microbial growth against different environmental factors. Good aseptic techniques were used to prevent contamination, resulting in a uniform set of results that are in line with the literature.

As expected, during the temperature test, the least amount of bubbles were emitted in tubes that had been exposed to extreme heat. The tube placed in boiling water yielded zero millimeters of bubbles. The boiling water denatured the enzyme and altered its chemical structure rendering it incapable of undergoing metabolic reactions. For these same reasons, the vile placed in a hot bath, containing water at 85 degrees, produced only one