Uses And Limitations Of Biosensors

There are many differents ways to identify a bacterial unknown and many different situations where identification would be beneficial. One way to identify bacterial unknowns is to perform biochemical tests. In this experiment multiple biochemical tests were done, by performing these tests on the bacterial unknown received the two different bacteria were then identified. The citrate test is done to test the ability of organisms to use citrate as a carbon source. This test uses Simmons citrate agar, the agar contains sodium citrate as the only carbon source and has bromothymol blue as the pH indicator. The organisms that use citrate as a carbon source use the enzyme to transport the citrate into the cell. The cells converts ammonium dihydrogen

The Unknown Bacteria 36/Bacteria # 2 on a TSA plate was examined by the naked eye and under a dissecting microscope. Bacteria # 2 was approximately 3 - 4 mm in diameter. They were circular in form with an entire margin and a flat elevation. The colonies were rough (granular), translucent, and white brownish color with black granules. The Gram stain resulted in a Gram negative rod. After the Gram stain was completed, the bacteria were streaked on an Eosin -Methylene Blue Agar plate and an Enterotube II was inoculated.

For many years the identification of microorganisms has been important in the world of medicine. It is essential or correct disease diagnosis in patients and for proper treatment. Knowing the correct identity and characteristics of microorganism is crucial when disease outbreaks occur in populations, also knowing how humans can benefit from microorganisms is important; many can be used in making certain foods or antibiotics.

Often scientists work with bacteria that do not come in a labeled test tube— for example, bacterial samples taken from infected human tissue or from the soil—and the scientist must then identify the unknown microorganism in order to understand what behavior to expect from the organism, for example, a certain type of infection or antibiotic resistance. However, because of the relatively few forms of bacteria compared to animals and because of the lack of bacterial fossil records due to their asexually reproductive nature, the taxonomy used to classify animals cannot be applied to bacteria (Brown 275). In order to classify unknown bacteria, a variety of physiological and metabolic tests are available to narrow a sample down from the fathomless number of possibilities into a more manageable range. Once these tests have been performed, the researcher can consult Bergey’s Manual of Determinative Bacteriology, a systematically arranged and continually updated collection of all known bacteria based on their structure, metabolism, and other attributes.

Today in medicine doctors are rapidly isolating and distinguishing the many pathogenic microbes encountered daily within the environment. Public health has been affected from the faster identification of microorganisms by delivering an accurate analysis to patients in order to receive treatment of the disease in a timely manner. Due to the growing understanding of these organisms more have been easier to indicate to improve water quality. Also more methods have been developed for better treatment options from fecal bacteria in public water systems. Scientist has developed such specific methods of identifying the unknown organism to tell if the contamination has come from either a human, bird, or mammal. (Achtman et al., 2008)

Bacteria are ubiquitous; they can be found on the skin, in the soil, and inside the body. Because of the very nature of this ubiquity, it is important to be able to determine between different strains of bacteria. An example of this is determining the causative agent for a disease so that the patient will be treated with the appropriate antibiotics. It may be important to determine the bacteria in a certain region, because like with enteric bacteria, it is normal to find them in the digestive tract as they are in a symbiotic relationship with our bodies in this area; however, they also cause opportunistic infections in places outside of the digestive tract to our detriment, such as with a urinary tract infection. Some strains of bacteria are common to nosocomial infections, and identifying these bacteria as such helps create the guidelines for healthcare workers in antiseptic technique. All of the morphology and characteristics of each strain of bacteria help us to better understand the role of bacteria in the body as well as helps us understand how they can cause illness, and what treatment regimen to set in place. In lab this semester, a sample of unknown

Preliminary studies help identify Genus species of bacteria. Two different preliminary study pathways must be used since two different pathogens were found in the sample. A dilution and a quadrant streak are the ideal methods to separate pure cultures of bacteria. MacConkey Agar and CAN (MAC) is a selective media that is used for the cultivation of gram negative bacteria. (PEA) is a selective media that is used

The identification of unknown organisms carries important ramifications that can be applied to many real world scenarios. In keeping with quality assurance beverages, food, cosmetics, and other products are frequently inspected for contaminants resulting from a presence of pathogenic bacteria. In medicine, a physician’s diagnosis and consequent treatment is largely determined from samples collected from infection sites that have been analyzed using microbial tests.

There are many reasons for identifying an unknown bacterium. The purpose of this exercise was to identify an unknown bacterium from a liquid culture. We chose our unknown bacteria from a rack of test tubes with several different species of bacteria inside. I wanted to pick an unknown bacteria with a number easy to remember so I pick the test tube labeled “745”. Procedures were followed as stated in the lab manual written by Dr. Pedro J.A. Gutierrez.

The bases of this experiment was to discover the identify of the unknown from three possible specimens: Klebsiella pneumonia, Escherichia coli, and Enterobacter aerogenes. Utilizaing the T streak technique, the bacteria was isolated into pure colonies for further study. The Gram Stain method was used to identity the morhphology of the bacteria such as the shape and whether the bacteria was Gram positive or Gram negative. Biochemical test were also used to help identify the unknown bacteria. The biochemical test used was the Triple Sugar Iron Agar, Sulfur Indole Motility test, Methyl Red test, Voges-Proskauer test, Citrate test, Urease test, and the Gelatin test. After observing the morphology of the bacteria using the Gram Stain method and utilizing all the possible biochemical test, the bacteria was identified to be Enterobacter aerogenes.

On June 25th, 2015 I chose the test tube labeled #19. This test tube contained an unknown bacterium, and the purpose was to determine the unknown bacterium by the end of the semester. Throughout the course, I ran a series of differential tests that would lead me to discovering the characteristics of my unknown. These tests that I will discuss in this paper are vital to understanding the biochemical mechanisms that different bacteria can perform, therefore helping me identify my bacterium based on molecular differences. During the course of this paper, I will refer to my unknown as unk#19. Also, I would note that aseptic technique was performed throughout the entire experiment and subcultures were regularly made.

A Gram stain was used to determine the morphology of the bacteria and to confirm that the bacteria were Gram-negative. After all of the differential media were inoculated, incubated and observed, unknown bacteria number 20 was determined to be Klebsiella pneumoniae. Introduction When bacteria are obtained from the environment, one needs to perform many differential tests on the bacterial species to identify it. First, the bacteria need to be obtained in pure colonies.

After inoculating an agar plate with the bacteria taken from a phone screen in Durham during winter, various tests were performed to attempt to identify the organism’s genus. We hypothesized that the bacteria was a member of the Staphylococcus genus. The Gram Stain results indicate that the bacterium is either Gram negative, but the KOH test indicates a Gram-positive isolate. Upon further consideration, we decided that the bacterium is a Gram-positive destainer. Gram-positive bacteria have a thick cell wall composed of peptidoglycan. As expected, the Gas Pak and TSA stab results indicate that the bacterium cannot grow in the absence of oxygen. A motility stab indicated that the bacteria were motile. Motility provides an ability to change direction and move away from repellents and toward attractants. Thus, the microbe can avoid unfavorable conditions, and live longer. The positive lysine decarboxylase test indicates that the microbe can use the amino acid lysine as a source of carbon and energy for growth. First, the bacteria use glucose as its primary carbon source, which causes the pH to drop. The enzyme lysine decarboxylase degrades lysine to produce basic products. This change in pH is what causes the broth to turn purple again, a positive result. An endospore stain indicated that the bacterium does not produce spores under stress to protect the cells from dying. Spores are metabolically inactive and

A fully formed biofilm now allows the individual bacterial cells to communicate with each other via quorum sensing. This activity helps cells pass information about their neighbors and surrounding environment to one

There were several experimental procedures that were performed by Bayry et al that allowed for this experiment to be performed. One of these procedures included treatment of an IgE antibody that is produced specifically in mice, SPE7 with heme using the technique immunoblotting to determine the polyreactivity of heme and the resulting consequences of the reaction. Immunoblotting, also known as western blotting, is a type of an assay that is specifically used for the detection and characterization of proteins1. According to Gallagher and Chakavarti, immunoblotting works by exploiting the specificity inherent in antigen-antibody recognition5. It involves the solubilization and electrophoretic separation of proteins, glycoproteins, or lipopolysaccharides by gel electrophoresis, followed by quantitative transfer and irreversible binding to nitrocellulose, PVDF, or nylon5. The immunoblotting technique has been useful in identifying specific antigens recognized by polyclonal or monoclonal antibodies and is highly sensitive5. This unit provides protocols for protein separation, blotting proteins onto membranes, immunoprobing, and visualization5. Another technique used was an Enzyme-Linked Immunosorbent Assay or ELISA. The purpose of an ELISA is to determine if a particular protein is present in a sample and if so, how much6. There are two main variations on this method and whichever one is used depends on the type of experiment that is being run. One can determine how much