Essay On Yeast

A mixed culture of two unknown bacteria was provided by the instructor. The methods used for

In the S. cerevisiae specimen, moderate growth was expected and observed based on the knowledge that most microbes desire this type of environment for growth. The same was expected although a larger amount of growth was observed for the S. epidermidis specimens in the 1% NaCl solution than expected. The 1% NaCl solution provided the best environment for the growth of both microbes. Minimal growth of S. cerevisiae and moderate growth of S. epidermidis was observed from the 7% NaCl solutions. The S. epidermidis is used to a slightly salty environment on the surface of skin which may account for the higher growth over S. cerevisiae in this environment. Lastly, no growth was noted in either specimen of 15% NaCl. This type of environment does not support the growth of most microbes due to the increase in salt content and the hypertonic environment it creates.

The purpose of this lab was to identify two unknown bacteria cultures using various differential tests. The identification of these unknown cultures was accomplished by separating and differentiating possible bacteria based on specific biochemical characteristics. Whether the tests performed identified specific enzymatic reactions or metabolic pathways, each was used in a way to help recognize those specifics and identify the unknown cultures. The differential tests used to identify the unknown cultures were oxidase, catalase, lactose and sucrose fermentation, Kugler/iron agar, nitrate reduction, gelatin hydrolysis, starch hydrolysis, manitol salt, MR-VP, citrate, bile esculin,

In this investigation pUC19 plasmids were used as the vector due to its small size of 2686bp, high uptake efficiency by the host and fast replication time. Important features of this plasmid include the origin of replication and multiple cloning sites (MCS). The origin of replication allows the plasmid to replicate inside the host bacterium. The MCS is located within the lacZ gene and contains unique sites for the Xbal & EcoRI restirction enzymes to cut and produce sticky ends for the CIH-1 gene to bind to. Furthermore, the pUC19 plasmid also contains an ampiccilin resistance gene so only transforemed E.coli are able to remain viable when spread on the agar plates that also has the addition of ampiccilin. The lacZ gene encodes the β-galactosidase enzyme which aids in indentifying the recombinant E.coli from the non recombinant cells (Coventry University 2016).

DNA. The isolated plasmids are ran on 40 ml 1% agarose gel at 110 volts with 1.2 μl 6X track

After the incubation period the bacteria was observed for pure colonies. The colonies were sampled and the three streak plate technique was repeated and this sample was incubated for forty eight hours at 37 degrees Celsius. After the incubation of the colonies, a gram stain was performed which is defined in the lab manual.

During the purification section of this lab, the LB/amp/ara agar plate was examined for well-isolated green colonies and the LB/amp plate was observed for white colonies with space between each other. These colonies were circled on the outside of the plates using a marker. Next, two 15 milliliter culture tubes containing 2 milliliters of nutrient growth media were obtained and labeled “+” and “-“. Using a new inoculation tube, the circled colonies from each plate were scooped out and immersed in their respective culture tubes. Once the bacteria was mixed into the solution, the tubes were sealed and placed horizontally into the 32⁰ incubator for 24 hours.

The field of biotechnology involves the concept of genetic engineering, altering the DNA/genetic material of an organism using information from a different one. The process in which bacteria can obtain this manipulated genetic information from another source is called genetic transformation. The goal of this experiment was to genetically transform Escherichia coli bacteria’s DNA by inserting the vector pGLO plasmid which codes for ampicillin resistance as well as the green fluorescent protein, GFP. For the experiment, the E. coli bacteria were separated into two groups; control and

A urea hydrolysis test was performed. A nitrate reduction was performed. The bacterial unknown was grown on Kigler 's iron agar media, MSA media, soy agar media, PEA agar media, EMB media, and SIM medium media. A gram stain was performed. A methyl red test was performed. A Voges-Proskauer test was performed. A citrate test was performed. A motility test was performed. A gelatin hydrolysis test was performed. A liquid broth agar was cultured to determine if there was use of oxygen.

Abstract When performing this lab, we demonstrated that Ecoli bacteria could have its DNA changed through a process called transformation. We inserted a plasmid for pGLO into the DNA of bacteria through a method know as heat shock. The pGLO was inserted in order to alter the phenotipic characteristics of that bacteria, and manipulate it's genetic code, so that it would glow when exposed to an ultra violet light.

The selected isolate Gur1 (6 mm disc) was grown on basal salt media supplemented with 2% carboxymethyl cellulose (CMC) at 28º C until substantial growth was recorded (Hankin and Anagnostaksis 1975). The Petri plates were flooded with congo red solution (0.1%), and after 5 min congo red solution was discarded. The plates were then washed with 1M NaCl solution, and allowed to stand for 15-20 min. The clear zone was observed around the colony when the enzyme had utilized by

Introduction Genetic transformation is known to be the conversion of a genotype into another with the addition of DNA from an external source. Frederick Griffith was the first person to use genetic transformation in 1928 with Streptococcus pneumoniae (Griffiths et al. 2000). There are three different methods that are used in genetic transformation to get the vector DNA into the nucleus of the competent cell. The methods are, projectile bombardment, electroporation, and heat shock. Heat shock is the most common method is projectile bombardment because it guarantees the mixture of the two DNA (APSnet…2014).

Objective: The purpose of today’s laboratory was to introduce a foreign gene into a cell using recombinant DNA technology by utilizing the techniques of DNA ligation and transformation of E.coli. Data was collected in the form of agar plates in order to analyze which colonies took up the vector alone and which colonies took up the

described in Materials and methods. (B) Two unique restriction sites (AsiS I and Swa I)

Before plating the strains on agar plates, dilutions of the three strains of cells were prepared with LB broth.