Agar Lab Report

Gelatin hydrolysis test is helpful in identifying and differentiating species of Bacillus, Clostridium, Proteus, Pseudomonas and Serratia [171]. Hydrogen sulphide (H2S) production test is used for the detection of H2S gas produced by an organism. It is used

This can be explained by the examining the medium in which they were grown in. The bacteria were transformed with the pGLO plasmid which contained the GFP and resulted in glowing bacteria, however, in order for this to occur the arabinose C sugar must be present in the medium. This sugar is responsible for the activation of the GFP6. Recall that in the E. coli cells in LB/amp +pGLO plate were also transformed but did not express the fluorescent glow. Even though they had the GFP gene in them, they were unable to express this protein without the arabinose C sugar to activate transcription of the

Nutritions, temperature, oxygen, pH, microbial products and antagonistic and synergistic effects are determinant factors which predispose the condition of residue of cutaneous normal flora populations. The ability of enzymes secretions in microorganisms is another factor for their colonization on the surface of the skin; because the presence of microbial extracellular enzymes on the human skin makes a wide range of nutrition accessible for microorganisms (12,

In the Oxidative fermentation tube the media was a differential media that helps determine whether specific bacteria can oxidize or ferment to metabolize glucose. Citrate test checks to see which bacteria could citrate as the only source of carbon. A positive test shows that an alkaline environment ia created and that the pH level rose. The color of the media changed from green to blue if its positive.

The next step is bacterial invasion or invasion by pathogenic products into the periodontal tissues, interactions of bacteria or their substances with host cells, and this directly/indirectly causes degradation of the periodontium, resulting in tissue destruction. As a Microbial Habitat, the mouth provides a warm and moist environment that suits the growth of many microorganisms. The mouth is the only site in the human body that normally provides non-shedding surfaces for microbial colonization; this facilitates the development of thick biofilms, particularly at stagnant sites. Thus, in this way, the host provides unique opportunities for biofilm formation in the mouth, and a secure haven for microbial persistence. Oral environment determines the constituent species of dental biofilm and the variation between individuals.

.4 Agar Disk Diffusion The antimicrobial tests were carried out according to disc diffusion tests (Lennette et al., 1985, Kim et al., 1995). Cells were streaked on MHA agar plate to obtain colonies at 37°C for 16 hrs after which they were resuspended in sterile saline solution to give an O.D of 0.1 at 600nm. On solidified 2% MHA plate, the bacterial culture is swabbed and sterile disc impression was made, 10 µl plant extracts was loaded on the agar plate.

On a filter paper or cotton bud, pick the desired colonies from the agar plate. Then, using a dropper, take the oxidase reagent and drop it on to the filter paper and observe for colour changes. The blue colour appearance indicates positive reaction whereas if there are no changes, then it’s a negative reaction. 3.12.3 Genus Verification using TCBS agar The TCBS medium, known as Thiosulfate Citrate Bile Salts Sucrose Agar is a recommended selective medium which allows the growth of bacteria belonging to the genera Vibrio.

Its virulence factor comes from multiple things within the cell and these things contribute to the types of infections they cause. Two important virulence factors are a secreted protein called coagulase and clumping factor. Some other virulent factors are the capsule, enterotoxins, exfoliatin, toxic shock syndrome toxin, and alpha toxin. The enterotoxins cause food poisoning in humans. The exfoliatin caused scalded skin syndrome.

Inducing Prodigiosin Transposon mutagenesis in Serratia Marcescens Introduction Serratia Marcescens is an opportunistic pathogen, mainly of healthcare facilities but can also be found in many diverse environments. Serratia is a gram negative bacteria which can give it innate resistance to certain antibiotics, especially those that target peptidoglycan cell wall synthesis, due to its outer membrane. In an environment with different microorganisms competing for food Serratia holds a component that gives it another selective advantage. The bacteria contains a red pigment called prodigiosin, that has antibacterial, antifungal, and even antiprotozoal activity.

Vitamin B12 is synthesized by the fungus Ashbya gossipy. Lipases, peroxidases, oxidases together with protease enzymes are used in the manufacture of detergents and biosurfactants that are used as household detergents, industrial cleaners as well as in leather

If there is a color change, then it is known that protein is present in the solution. Finally, lipids are tested. 5 mL of water are added to 5 mL of oil. 5 drops of Sudan 3 are added, and if the color changes, then lipids are present. Next, the McMush is tested.

Being able to identify unknown microbes from systematic testing is what makes the field of microbiology so important, especially in infectious disease control. Using the testing procedure laid out by the microbiology field we are able to identify unknown bacteria present in our everyday lives, and along the way learn a lot about their characteristics that separate them from other types of bacteria. Being able to do this is vital in order for us to understand why microbes are present in certain places, how they are able to grow and what restricts their growth, that way they can be combatted if necessary. These techniques for determining unknowns are also important for isolating and testing infectious disease microbes in order to prevent spreading. Another important aspect of being able to identify unknown microbes is the

Good and bad bacteria exist in our environment, depending on which one enters the body the immune system these bacteria can either compromise or aid the immune system’s illness fighting capabilities. In class we learned that the skin aids in fighting infection by acting as a protective barrier. In addition, we discussed how normal flora is found on the skin and aids in the defense mechanism because it fights off potential threats by competing with them. The normal flora consists of microorganisms such as protozoa, fungi and bacteria.

coli bacteria new traits. The pGLO plasmid that is being transformed into these cells contains genes that can give colonies of bacteria the ability of antibiotic resistance and a green fluorescent glow. Four different models were prepared and plated on multiple agar plate. After the bacteria was grown for three days in an incubator at 37°C; observations were made and recorded (Table 1). All of the plates were looked at for the amount of colonies grown, if growth was present, and if the colonies gained the ability to glow green.

To begin the process, a pre-prepared 1% agarose gel was obtained. The gel chamber was set up by placing the agarose gel into the chamber and submerging it in plentiful TAE buffer. The wells were filled with both PCR and DNA and shared between six students. The wells were labeled 1-7. The first well was pre-loaded with DNA ladder and labeled as 1 microliter kb DNA ladder.