Identifying The Identification Of Bacteria

An unknown bacterium was handed out by Dr. Honer. The appropriate tests were prepared and applied. The first procedure that was done was the gram stain. Under a microscope, if the gram stain is purple, the bacterium is gram positive, if the stain is red, it is gram negative. The next test was the fermentation tests for glucose, sucrose and

The purpose of this lab was to identify an unknown bacteria culture using differential tests. The identification of the unknown culture was accomplished by identifying the bacteria based on its specific metabolic characteristics and morphology. It is suggested that culture 11 is a sample of Enterobacter aerogenes.

Depending on what a bacteria can and cannot do, will help to correctly identify it. It is always important to start out with a purity check. To achieve that, you can inoculate an agar plate and incubate for 48 hours. Make sure you only see one type of colonies on the plate. Knowing the optimal temperature for the bacteria will also let a scientist know where to place the different types of medias he/she inoculates with the unknown bacteria. Knowing if you are working with a gram positive or gram negative bacterium, a scientist will need to perform a gram stain. This will also help to see the shape and arrangement of the bacteria. The size can be determined by doing a simple stain. The size of most bacteria ranges from .5- 10um. This specific bacteria that I was working with, was smaller than 2um. Most bacteria can grow with the presence of oxygen. A simple test like the gas pack can be performed to figure out if growth is possible without oxygen is doable. My unknown bacteria needs oxygen to grow. Throughout my study, the unknown bacteria was tested to see if it can grow in acidic conditions, however no growth occurred. Before inoculation, the substrate was a clear yellow color and in liquid state. After receiving the negative result, I kept the broth in the 37C incubator for 7 more days to confirm the negative result. Using premade slants with different types of sugars such as Mannitol, Sorbitol, Lactose, Trehalose, Maltose and Sucrose, to determine if the bacteria can metabolize glucose and if the bacteria is oxidative or fermentative. It was determined that my bacteria is strictly oxidative (needs oxygen to grow) and cannot metabolize glucose. Another test was done to confirm if the bacteria was able to utilize different carbohydrates in the presence of oxygen. I used Cellobiose, Arabinose, Adonitol, Fructose and Malonate wee tabs. Out of the 5 different types of carbohydrates, only 3 different

The purpose of this lab was to identify two unknown bacteria from a mixed culture. The reason for identification of unknown bacteria was to help students recognize different bacteria through different biochemical tests and characteristics. This is important in the medical field because identification of unknown bacteria can help treat a patient by knowing the contributing source of a disease. Also knowledge of different bacteria helped others make antibiotics used today. This lab was completed by using the methods learned thus far in identification of bacteria.

The purpose of this study project was to carefully isolate and identify two unknown bacteria from a mixed culture. The ability to properly evaluate biochemical test results is also necessary for the identification to be successful. The goal was to apply all of the methods and techniques that have been learned in the microbiology laboratory course for the proper identification of unknown bacteria. A certain amount of bacteria that were used throughout the course were possible bacteria that could be found in a mixed culture. The bacteria that were identified in the mixed culture were Staphylococcus Aureus and Kocuria Rhizophila.

The first result of importance was the result of the Gram stain. The observations of the unknown bacteria from the slant culture after Gram staining showed that the unknown bacteria were Gram negative bacilli (Image 1). After determining the unknown bacteria was Gram negative, an oxidase test was conducted on a sample from the slant culture. The cotton swap with the sample of bacteria did not change color when the oxidase reagent was applied, thus providing a negative result. With a negative oxidase test, further tests were conducted to determine various characteristics of the unknown bacteria. A MR-VP broth was inoculated with a sample from a slant culture of unknown bacteria. After incubation, the methyl red reagent was added to the broth, and the broth turned red, providing a positive result (Image 2). An EMB agar streak plate was inoculated with a sample from a slant culture of the unknown bacteria, and after incubation, growth was found on the plate, providing a positive result (Image 3). A Citrate agar slant was inoculated, and after incubation, growth was found on the media, providing a positive result (Image 4). A Urea agar slant was inoculated, and after incubation, the agar had changed from a peach color to a bright pink color, providing a positive result (Image 5). Using the flowchart (Figure 1) developed from the Table of Expected Results, the lab partners started at the oxidase test. Given the negative result of the oxidase test, the flowchart is

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

Bacteria is a single celled organism, bacteria have evolved to thrive in almost any environment and can be found in almost any substance/surface and also in the human body, only 1% of bacteria is actually harmful.

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

There are many reasons for knowing the identity of microorganisms. The reasons range from knowing the causative agent of a disease in a patient, so as to know how it can be treated, to knowing the correct microorganism to be used for making certain foods or antibiotics. This study was done by applying all of the methods that have been learned so far in the microbiology laboratory class for the identification of unknown bacteria. The identification process can be completed with a series of deferential stains and biochemical tests. Creating a dichotomous key helps to limit the amount of biochemical tests done on an unknown organism and by observation

A Dichotomous Key was studied to identify bacteria and their relationships. Some of the organisms at the end of the Dichotomous Key had viable characteristics that separate them from different groups, and those that did not students learned how to further classify them. A Dichotomous Key is used to narrow down the search for the unknown organism tested. It is organized by phenotypic characteristics of organisms and conducts a systematic way of identifying the other unknowns. In the lab students were given a tube labeled with a number. Instructions were given to conduct a Gram stain to begin the search followed by the use of a Dichotomous Key and photos as resources to carry out the search. Instructions read to isolate and identify the unknown bacterium with both differential and selective tests to positively identify the given unknown organism. Differential tests used specifically for this unknown microorganism was BEA (Bile Esculin Agar), which interpreted results by the hydrolysis of esculin when the media is blackened around

The purpose of this study was to identify the unknown bacterium using biochemical tests and various methods that had been learned from previous the microbiology laboratory class. Identifying the unknown bacterium was determined by separating and differentiating possible

Before, biologists assumed all microbes are bad for the human body (automatically thought of pathogens), caused many diseases and harm our body fundamental systems. In addition, the biologists think that our body is already built which had all the functions required to maintain our health. However, the attitude has changed over the last decade. The biologists characterized the most prevalent species of microbes in the body, and found out that these collective microbes do not threaten us, and they also are important part of human bodies.

When we speak of the word “bacteria” some individuals may not recognize how large of a role these tiny organisms play in our everyday lives. Some may jump to the conclusion that bacteria are related to the spread of germs or sickness among the human population. Most microbes are harmless or beneficial (Matthews, 2015) and a large majority of these tiny microbes are extremely important in order to maintain the balance of living organisms and chemicals in our environment (Tortora, Funke, & Case, 2013).

Life on this planet began with microorganisms. Through millions of years microorganisms have found ways to successfully adapt and survive. These adaptations have created a wide biodiversity, allowing them to basically populate in all places. Why are these microbes so important? Because they shape the history of our world. Some microbes can be deathly to humans while some others are favorable, for example, bacteria that lives in the gut of both humans and animals and helps during the process of digestion (Alfred Brown & Heidi Smith, 2006). Understanding these interactions help scientists to find ways to protect humans from potential deathly pathogens. In order to observe microbes, microscope proficiency and microorganisms’ identification are crucial skills in a microbiology lab. During this laboratory session, samples of environmental and human organisms were inoculated into two different rich media and incubated to their according temperature. After this, appropriate use and calibration of the microscope was performed. Lastly, morphology and size of different species of bacteria, algae, fungi and protozoan were recorded.