The unknown microorganism in question is believed to be Pseudomonas fluorescens. This bacterium is an obligate aerobe possessing multiple polar flagella for motility purposes and flourishes in twenty-five to thirty degree Celsius environments (microbe wiki 1). It also produces siderophore pyoverdine which is responsible for chelating iron when environmental concentrations are low (microbe wiki 1). These siderophores are responsible for this microbe’s ability to fluoresce under ultra violet light (microbe wiki 1). The process of identifying this microbe began by performing a Gram’s stain (see image #1, page 7). Pseudomonas fluorescens is a gram negative bacillus shaped bacterium. Following the establishment of the microorganism’s Gram stain …show more content…
This gram negative bacterium inhabits soil, plants, and water surfaces (micro wiki 2). Certain strains of this bacterium reside in the rhizosphere of plants where it is able to produce secondary metabolites, including antibiotics against some soil borne plant pathogens (Ganeshan 123). Pseudomonas fluorescens shares a commensal relationship with the plant that it lives on. The bacterium receives nutrients and environmental protection from the plants, and in turn the microorganism provides key nutrients, degrades pollutants, and produces antibiotics which protects against the plant’s pathogens (Ganeshan 124). Currently, research is underway which is evaluating the significance of the microbe’s ability to be used as an alternative to synthetic pesticides (micro wiki 2). Pseudomonas fluorescens is toxic to the larvae and pupae of vector mosquitos, as well as having the ability to produce antibiotics and hydrogen cyanide which can kill other microbes, including fungi Ganeshan 124). While this microbe possess the potential to have a positive impact on the farming and agricultural industry, Pseudomonas fluorescens also positively effects human
Upon receiving the unknown Microorganism (M.O.) #16, I prepared a slide by cleaning and drying it. Then, using a bottle of water I placed sterile drop of water on the slide and used an inoculating loop, flame sterilized, I took a small sample of the unknown growth in my agar slant and smeared it onto the slide in a dime sized circle and then heat fixed it for ten minutes. After ten minutes had passed, I collected the ingredients needed to perform a gram stain. I got the primary stain, crystal violet, and flooded my smear for sixty seconds, and then rinsed the color off with water until the water ran clear. I then flooded the smear with the mordant, grams iodine, and let that sit on the slide for sixty seconds as well. I then rinsed the grams iodine off with water and applied alcohol to the smear to decolorize the cells; however I made sure not to over decolorize and only put enough drops on the smear till the purple ran clear. I then rinsed the slide with water and flooded the smear with safranin the counter stain and let it sit for sixty seconds and then rinsed the color off with water. I blo...
Serratia marcescens, a Gram-negative bacillus, was originally and solely considered a biological marker in the medicinal industry, due to its highly natural red pigment: Prodigiosin (Hejazi and Falkiner, 1997). The pigment has numerous roles within bacteria, which can be further translated into the pharmaceutical and medical domain. This bacterium naturally occurs in water, soil, on plants as well as in humans and animals (Khanafari et al, 2006), where it is deemed an opportunistic pathogen.
After 5 days of growth each slant was tested using the gram staining technique to confirm the complete isolation of the bacteria. Both isolations were completely successful. Then each sample of bacteria was subjected to a series of tests for identification.
The Gram positive bacteria has been nicknamed Posi. The Gram positive species’ morphology includes having an opaque opacity with a smooth margin. The moisture content of the Gram positive species is shiny and the pigmentation is gold. The Gram positive species grows at an optimal temperature of 37°C. The shape of the Gram positive species is a cocci, with an arrangement of grapelike clusters. The Gram positive species’ size ranges from .5-1.5 µm. Oxygen requirement of the Gram positive species is facultative, and has complete lysis of red blood cells. All results are summarized in Table
The results of these tests prove that the unknown organism is Citrobacter freundii hereby referred to as C. freundii. C. freundii is a member of the Enterobacteriaceae family, like all the other unknowns given in this test. The species is a facultative anaerobic and is a gram-negative bacilli. C. freundii is a non-spore forming, motile bacteria that are long rod-shaped with a typical length of 1-5 μm.
The results of the gram stain test were cocci and purple. This indicated that the unknown bacteria were gram positive. The gram stain test eliminated Escherichia coli, Klebsiella pneumonia, Salmonella enterica, and Yersinia enterocolitica as choices because these bacteria are gram negative. Next a Blood Agar plate was used because in order to do a MSA or a Catalase test there needs to be a colony of the bacteria. The result of the Blood Agar plate was nonhemolytic.
The purpose of this laboratory is to learn about cultural, morphological, and biochemical characteristics that are used in identifying bacterial isolates. Besides identifying the unknown culture, students also gain an understanding of the process of identification and the techniques and theory behind the process. Experiments such as gram stain, negative stain, endospore and other important tests in identifying unknown bacteria are performed. Various chemical tests were done and the results were carefully determined to identify the unknown bacteria. First session of lab started of by the selection of an unknown bacterium then inoculations of 2 tryptic soy gar (TSA) slants, 1 nutrient broth (TSB), 1 nutrient gelatin deep, 1 motility
The Gram stain is a system used to characterize bacteria based on the structural characteristics of their cell walls. A Gram-positive cell will stain purple if cell walls are thick and a Gram-negative cell wall appears pink. Most bacteria can be classified as belonging to one of four groups (Gram-positive cocci, Gram-positive bacilli, Gram-negative cocci, and Gram-negative bacilli) (Phenotypic analysis. (n.d.).
In the last decade, the number of prescriptions for antibiotics has increases. Even though, antibiotics are helpful, an excess amount of antibiotics can be dangerous. Quite often antibiotics are wrongly prescribed to cure viruses when they are meant to target bacteria. Antibiotics are a type of medicine that is prone to kill microorganisms, or bacteria. By examining the PBS documentary Hunting the Nightmare Bacteria and the article “U.S. government taps GlaxoSmithKline for New Antibiotics” by Ben Hirschler as well as a few other articles can help depict the problem that is of doctors prescribing antibiotics wrongly or excessively, which can led to becoming harmful to the body.
Bacteria play a large role in our health, the environment, and most aspects of life. They can be used in beneficial ways, such as decomposing wastes, enhancing fertilizer for crops, and breaking down of substances that our bodies cannot. However, many bacteria can also be very harmful by causing disease. Understanding how to identify bacteria has numerous applications and is incredibly important for anyone planning to enter the medical field or begin a career in research. Having the background knowledge of identifying an unknown bacteria may one day aid healthcare professionals diagnose their patient with a particular bacterial infection or help researchers determine various clinical, agricultural, and numerous other uses for bacteria.
The first step to the unknown is selecting an actual organism. The best way to select a culture is based on a high-quality distribution. Equally important, shaking up the broth tube facilitates in the distribution. Upon selection, a gram check for purity is performed. Step by step instructions for this procedure can be found in Benson’s, Microbiological Applications p. 99. Furthermore, an aseptic technique must be performed for this test and the entire tests following the unknown. The purpose of this test is to differentiate between gram positive and gram-negative bacteria. The key indicator of gram-positive bacteria is a purple stain and a pink stain for gram-negative bacteria. A slide is viewed with a microscope under oil immersion. Equally
Talaro , K., & Chess, B. (2012). Foundations in microbiology. (8th ed., pp. 563-564). New York, NY:
Bacterial cells, like plant cells, are surrounded by a cell wall. However, bacterial cell walls are made up of polysaccharide chains linked to amino acids, while plant cell walls are made up of cellulose, which contains no amino acids. Many bacteria secrete a slimy capsule around the outside of the cell wall. The capsule provides additional protection for the cell. Many of the bacteria that cause diseases in animals are surrounded by a capsule. The capsule prevents the white blood cells and antibodies from destroying the invading bacterium. Inside the capsule and the cell wall is the cell membrane. In aerobic bacteria, the reactions of cellular respiration take place on fingerlike infoldings of the cell membrane. Ribosomes are scattered throughout the cytoplasm, and the DNA is generally found in the center of the cell. Many bacilli and spirilla have flagella, which are used for locomotion in water. A few types of bacteria that lack flagella move by gliding on a surface. However, the mechanism of this gliding motion is unknown. Most bacteria are aerobic, they require free oxygen to carry on cellular respiration. Some bacteria, called facultatibe anaerobes can live in either the presence or absence of free oxygen. They obtain energy either by aerobic respiration when oxygen is present or by fermentation when oxygen is absent. Still other bacteria cannot live in the presence of oxygen. These are called obligate anaerobes. Such bacteria obtain energy only fermentation. Through fermentation, different groups of bacteria produce a wide variety of organic compounds. Besides ethyl alcohol and lactic acid, bacterial fermentation can produce acetic acid, acetone, butyl alcohol, glycol, butyric acid, propionic acid, and methane, the main component of natural gas. Most bacteria are heterotrophic bacteria are either saprophytes or parasites. Saprophytes feed on the remains of dead plants and animals, and ordinarily do not cause disease. They release digestive enzymes onto the organic matter. The enzymes breakdown the large food molecules into smaller molecules, which are absorbed by the bacterial cells. Parasites live on or in living organisms, and may cause disease. A few types of bacteria are Autotrophic, they can synthesize the organic nutrients they require from inorganic substances. Autotrophic bacteria are either photosynthetic or Chemosynthetic. The photosynthetic bacteria contain chlorophyll that are different from the plant chlorophyll. In bacterial photosynthesis, hydrogen is obtained by the splitting of compounds other than water.
The objective of our project was to determine if different wavelengths of light would affect the growth of the Rhodococcus genus and whether the two bacteria would handle DNA damage from UV light exposure differently. Our hypothesis is that various wavelengths of light would inhibit the growth of bacterial colonies of both Rhodococcus species differently. Also, we believe that Rhodococcus fascians (yellow) is more resistant to DNA damage from UV light than Rhodococcus corynebacterioides (red). To perform this experiment, we first made the bacterial growth medium was made. Then, the process of the dilution of the bacteria is performed to allow the bacteria to be seen easily. The diluted bacteria is spread upon the medium in the petri dishes
Microbes are everywhere in the biosphere, and their presence invariably affects the environment in which they grow. The effects