...Introduction Bacteria are microscopic unicellular prokaryotic organisms characterized by the lack of a membrane-bound nucleus and membrane-bound organelles. They are remarkably adaptable to diverse environmental conditions and are found in bodies of all living organisms and on all parts of the earth. The purpose of microbial biochemical tests is to identify the unique traits it yields and with that knowledge we can then categorize them in groups and specify them by scientific name. These experiments included the Triple-sugar iron agar (TSIA), Sulfur Indole Motility (SIM), Methyl Red (MR), Voges-Proskauer (VP), Citrate, Urease, Gelatin, and Oxidase Test. In order for these tests to produce reliable and credible results, the bacterium organism must be grown using strict and meticulous procedure to produce viable colonies of pure culture. Having pure culture is significant to ensure that a single type of bacteria is used for identification without contamination so tests can be run without complications or confusion. Once all these tests are performed, the unknown bacteria in this lab will be one of the following: Escherichia coli, Enterobacter aerogenes, Proteus mirabilis, Klebsiella pneumoniae, or Salmonella typhimurium. This report included the results and details to these experiments which are discussed further on. Abstract Gram negative bacteria Unknown #12 was run through an array of tests which produced positive and negative results. The results obtained from the various...
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...Microbiology is requires not only an academic understanding of the microscopic world but also a practical understanding of lab techniques and procedures used to identify, control, and manipulate microorganisms. The proper identification of a microorganism is not only important in a microbiology lab but also in the medical, industrial, and pharmaceutical fields. In this lab report, lab techniques and procedures learned during this course were performed to assess each students’ practical knowledge in microbiology. 6In area of fields I mention earlier microbiology is very important to our vaccination and antibiotics we are using, understand that microorganism play a key role in maintaining life on earth, fixing gases and breaking down dead plant and animal matter into simpler substances that are used at the beginning of the food chain 6. Biotechnologists can also exploit the activities of microbes to benefit humans, such as in the production of medicines, enzymes and food. The goal of this lab report is 1) to demonstrate comprehension of the methods and lab techniques learned during the semester 2) to explain the tests performed on each isolated unknown that led to the identification of each unknown 3) and to give a background on the characteristics, pathogenicity and some uses of one of the identified unknowns. II. Introduction In this lab report I will discuss how I came to find my two unknown bacteria. Each bacteria have undergo many different test to eventually identifying...
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...gained information can be used to identify bacteria. A scientist by the name of David Bergey was the first person who proposed the system of bacterial classification in which bacteria are grouped according to Gram reaction, metabolism, and morphology. The first edition of Bergey’s Manual of Systematic Bacteriology was published in 1984. This book can be used to identify a microorganism. The purpose of this experiment is to identify an unknown bacteria using the skills learned in microbiology laboratory this semester. Materials and Methods This experiment was conducted at Louisiana State University in Shreveport...
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...Systematic Methodology used in the Identification and Isolation of Escherichia coli and Bacillus cereus from an Unknown Culture. By: Richard Martinez MCB-2010L Microbiology Lab Dr. James Rogers 11/29/13 Unknown bacteria were determined to be Escherichia coli and Bacillus cereus due to their morphological, physiological and metabolic properties. I. Abstract In a laboratory setting, it often becomes necessary to identify an unknown organism. In this experiment, researchers classified some unidentified bacteria based on their physical structure, colony morphology, optimal conditions and metabolic properties. A Gram stain using crystal violet, iodine, and safranin and a simple stain using methylene blue characterized the organism’s cell walls. Cultural behaviors were classified by inoculating the organisms onto nutrient agar and incubating them at 30° and 37° C for 48 hours, and observing their behaviors, as well as using Mannitol and phenol red media for fermentation and acid production. Optimal growth temperatures were determined by incubating nutrient agar plates of the organisms at 30° C and 37° C. The metabolic profile was created by inoculating the bacterium into broths containing lactose, mannitol, and citrate and incubating the tubes at 30° and 37° C for 48 hours, then observing them for color change. The stains revealed that the bacteria were both Gram-negative and Gram-positive bacilli. Organism “A” was shown to not grow on MacConkey agar and to have...
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...Unknown Identification Introduction to Microbiology Lab Professor M Biology Lab 1913 11/11/2014 I. Introduction A series of tests was completed in order to identify an unknown microorganism. A gram stain reaction test was done. A gram stain reaction test is used to differentiate between two bacterial species. The two species; gram positive and gram negative bacteria have varying properties of their cell wall structural composition. The gram positive bacteria contain a thick peptidoglycan layer in their cell wall which retains the primary crystal violet stain. The crystal violet is washed from the fixed stain and gram-negative bacteria appear red after the decolorizer washes the primary stain due to their more porous higher lipid content walls and the safranin counter stain adheres to their thinner cell wall. The microscopic examination of the bacteria after staining allows for the morphology of the organism to be determined because as the cell is killed during the staining process it retains its rigid structure allowing for morphology determination. A fermentation test was done. Three different carbohydrates are used to determine whether the organism can ferment a sugar as well as if a gas is produced during heterofermentation. A phenol red broth is used which retains a red color at a pH of 7.4 indicating no fermentation of a sugar. When an acid is produced during fermentation, the pH of the broth will lower and the broth will turn yellow. The sugars...
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...Determination of Two Unknown Organisms From Sample number 16 Intro: This was an experiment to identify two unknown organisms from sample number 16. The importance of this experiment is to identify two differential bacteria that are commonly found in the world and in the presence of everyday life. Considerations of organisms that could be in the unknown tube include, but not limited to Bacillus subtilis, Clostridium sporogenes, Serratia marcescens, Micrococcus roseus, Micrococcus luteus, Sarcina lutea, Staphylococcus epidermidis, Alcaligenes faecalis, Pseudomonas fragi, and Escherichia coli. The goal of this experiment is to use scientific method by demonstrating proper lab techniques, observing and collecting data, then analyzing results to...
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...HOW TO WRITE AN UNKNOWN LAB REPORT IN MICROBIOLOGY GENERAL Unknown reports in microbiology are written in scientific format. Scientific writing is written differently from other types of writing. The results of the exercise or experiment are what are being showcased, not the writing. The purpose of scientific writing is not to entertain, but to inform. The writing should be simple and easy to understand. There is a specific style that must be followed when writing scientific reports. Scientific writing is typically written in the passive voice. The pronouns "I", "We" and "They" are not typically used.. For example, instead of writing "I used a TSA agar plate to isolate my unknown," it is customary to write, "A trypticase soy agar (TSA) plate was used to isolate the unknown." It is also customary to write in the past tense for most of the report. This includes the introduction, the summary, the description of the materials and methods and the results. The present tense is reserved for the conclusions about the results. See the examples given below. Some other general rules that should be followed are: Microbial nomenclature: The name of the bacterium should written and spelled correctly. The name should be italicized or underlined. Italicized is preferred. For example, Staphylococcus aureus. The genus is capitalized but the species is not. After the full genus name is given in the paper, it can be written as S. aureus, but still italicized. This is as long as there in no other...
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...Antibiotic Resistance and Gram Staining of Unknown Bacterial Samples Microbiology Lab July 1, 2013 Abstract: In this final laboratory assignment, each student was given an agar plate. Each plate was swiped with a pure culture bacteria sample. Where the sample came from and what kind of bacteria was unknown to the students. We were asked to observe the colony morphology on our plates and to perform the antibiotic sensitivity/resistance test. The plates were put into a 37° incubator oven. The next day the plates were taken out of the oven and we calculated the zone of inhibition. We then performed a gram stain of our bacteria and analyzed it under a microscope. We were then able to assess what kind of bacteria we had and if it was gram positive or negative. Introduction: Simple staining (the use of a single stain) allows a microbiologist to observe the morphology (shape) and arrangement of bacteria. In order to classify bacteria into different groups a differential staining procedure must be done. A differential stain involves the use of two or more stains. Depending on the components of the bacterial cell wall or outer layers, the bacteria will either retain the primary stain or have the primary stain removed in a decolorizing step and then retain the secondary stain. The gram stain is the most common differential stain used in the microbiology laboratory to categorize bacteria. The primary stain is the cationic dye Crystal violet and the secondary...
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...Unknown bacteria determined to be Alcaligenes faecalis because of its morphological, physiological and metabolic properties. In a laboratory setting, it often becomes necessary to identify an unknown organism. In this experiment, researchers classified an unidentified bacterium based on its physical structure, colony morphology, optimal conditions and metabolic properties. A Gram stain using crystal violet, iodine, and safranin and a simple stain using methylene blue characterized the organism’s cell wall. Cultural behavior was classified by inoculating the organism onto nutrient agar and incubating it at 37° C for 48 hours, and observing its behavior, as well as using SIM medium to test for motility. Optimal growth temperature was determined by incubating nutrient broths of the organism at 25° C and 37° C, and optimal pH was tested by inoculating broths with pHs of 3, 7, and 10. Fluid thioglycollate medium determined the organism’s oxygen requirements. The metabolic profile was created by inoculating the bacterium into broths containing glucose, lactose, mannitol, and citrate and incubating the tubes at 25° C for 48 hours, then observing it for color change. Oxidative metabolic tests for oxidase and catalase were also performed using an oxidative reagent and hydrogen peroxide, respectively. The Enterotube II System was used to further classify its metabolic profile. The stains revealed that the bacterium was a Gram-negative bacillus. The organism was shown to be non-motile...
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...Weekly iLab iLab: Exploring the Microbiology Lab FirstName Tiffani_LastName: Whitehead Section 1 Lab Safety 1. There are four safety equipment items that a lab should have. Identify two of these four items. (2 pts) Biological Safety Cabinet, Eyewash and shower 2. Identify one of the three ways to keep your work area safe. (1 pt) Keep your workspace free of all unnecessary materials 3. There are five recommendations for dressing properly in a lab environment. Name two of these recommendations. (2 pt) Avoid loose fitting items of clothing, Wear appropriate shoes sandals are not allowed. 4. There are several safety tips to protect one’s mucous membranes and broken skin. Identify one of the recommended tips. (1 pt) Do not apply makeup, put in contact lenses, or otherwise perform activities that might introduce lab organisms to your personal space. 5. When working in a microbiology lab, it is important to contain spills and discard materials properly. Describe how a spill should be cleaned up safely in a microbiology lab. (3 pts) 1. Wear a lab coat, disposable gloves, safety glasses or a face shield, and if needed, approved respiratory equipment. 2. Soak a paper towel(s) in an appropriate disinfectant (70% ethanol or fresh 10% bleach solution) and place around the spill area. 3. Working from the outer edges into the center, clean the spill area with fresh towels soaked in the disinfectant. Be sure to decontaminate any areas or surfaces that...
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...positively best bacteria to receive when doing an unknown project The word bacteria receives a bad connotation in the everyday world but some may not realize the importance bacteria has on a person’s immunity and health. There can be both good and bad bacteria. Good bacteria, for example, helps to breakdown food enabling the digestion process to work smoothly and absorb nutrients like probiotics. These good bacteria are often found in foods like yogurt, cheese, and sauerkraut. Best of all, good bacteria can help treat infectious diseases. A study has shown that, when injected with a good predatory bacteria like Micavibrio aeruginosavorus and Bdellovibrio baceriovorus, an antibiotic resistant bacteria was defenseless (Nordqvist, 2013). The study was created for an eye infection to see whether good bacterial pathogens would be able to fight off bad bacterial pathogens without damaging the eye or causing further irritation. The term microbiology means the study of microscopic organisms. Within the specialized area, microbiologists help to identify new organisms and how they affect life on earth. There are new organisms being discovered every day, and there could be dangers or losses without proper identification of how they live, what they do, and can they be controlled. A study was done to show the process of categorizing and identifying an unknown organism. Throughout the semester, multiple tests were performed to distinguish between the different types of bacteria and characteristics...
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...of industries and pollution rates are more affected by the bacteria and the difference in the cell biology growth process. Also the difference between the growth processes in one land verses another. This article did hold my interest throughout reading it to the end. I had a hard time at first understanding what they were doing and how. I don’t feel like they explained how as much as what they were doing. Understanding what they were meaning took extra research to clarify meanings to the type of research and the components to what they were researching. Also the microbiology components and the different types of cells, are unknown areas of knowledge to me. So again it took some extra research and definitions to understand exactly what they may have been talking about and the different processes to the components that made up this process and outcome. This article helped my interest in economy and the life to life. To me the world and its natural resources that it with holds are slowly changing due to the economic changes we have inquired and worries me of the long term outcomes we will be facing in decades to come. I wish we recognized this more and acted upon it more. I feel like we are stuck in the mind set of businesses and advancing in technology that isn’t really looking into the earths affect and even human and animal’s long term affect. What I got from this first article, is basing its research in microbiology in cell biology. This article starts itself with explaining...
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...Bio 15 – Microbiology Final Unknown Report Sheet Unknown # ___90___ Genus and species of unknown _______Escherichia coli_________ Gram reaction and morphology ____Gram Negative reaction/Translucent and Shiny___ Other stains performed and results: Results: Please list the test results for all tests that were performed on the unknown. For tests not performed, write ND. |Carbohydrates: |IMViC Tests: | |Glucose |AG |Indole |+ | |Lactose |+ |Methyl Red |+ | |Mannitol |AG |Voges Proskauer |_ | | | |Citrate |ND | | | |Additional Biochemical Tests: | |Oxidase |_ |Lysine decarboxylase |+ | |Catalase |ND |Ornithine decarboxylase |ND...
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...Process and Techniques of Finding Unknown J Abstract: As part of a focal study within Microbiology, many scientists have endeavored to identify the many species and types of microbes found in different environments. In an effort to categorize, understand and distinguish one microbe from another, scientists developed tests to show unique characteristics of microbes. This experiment enlists these tests, such as PCR, Simple and Gram staining, anaerobic growth tests, IMViC, Catalase, Oxidase, selective and differential media to identify an unknown microorganism. The Unknown organism studied was labeled “J” and found to be a gram negative, rod shaped bacteria that does not produce endospores. The selective and differential agars produced no growth on the MSA agar plate showing that the bacteria did not favor a salty environment of the Mannitol salts and showed an acidic by product in the selective and differential media of MacConkey’s Agar. The bacteria showed to metabolize sugars but did not produce any gaseous byproducts. After 16s rRNA was processed and run through a PCR, electricphoresis was used to run the RNA out on a gel in order to sequence the RNA which was then compared in a database. Furthermore, the Unknown J did not produce or metabolize starch. The bacteria did not react with the Citrate, KEY oxidase. When compared to other known bacteria tested, unknown J proved to be Escherichia coli. Introduction: Identifying bacterial causes for certain diseases that have...
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...Unknown Bacteria Lab Report #21 In Microbiology Lab, we learn the scientific method of streaking, staining, microscopy, aseptic culture, and selective and differential tests. These tests will help me identify my Unknown Bacteria. The first procedure I did was the isolation streak of my unknown out on a Trypticase Soy Agar. The purpose of Trypticase Soy Agar is to provide enough nutrients of the microorganism to grow. After I finish my isolation streak, my plate were incubated and grown. Once I got my plate to look at my results and I realize I started my streaking pattern wrong. Because of the way I started my streaking pattern I wasn’t able to see my own results. However, I did my own research of how my plate should have look like if I had did my streaking right. With an educated guess of my unknown species, the results I found for the plate have colonies agar that are tan- pigment, convex, circular, and smooth. The cells are also motile rods. The colonies can be observed under Ultraviolet Light. The second procedure was to perform a Gram stain. The purpose of the Gram stained method is to differentiate between a Gram positive and Gram negative organisms and also learning about the cellular morphology and arrangements. I carefully prepare a slide smear on three slides and then started the Gram stain procedure. Once the procedure was done, all three of my slides had a pink stain which automatically figured that my unknown bacteria was Gram negative. Then I examine the finished...
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