Microbio lab report body Essay example

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

This lab experiment was done for the purpose of learning how to determine a gram negative bacterium based on multiple tests learned throughout the semester. My gram negative unknown bacterium given to me was Salmonella typhimurium based off of the following tests; Triple Sugar Iron Agar (TSIA), Sulfate Indole Motility (SIM), Methyl Red (MR), Voges-Proskaur (VP), Citrate, Urea Hydrolysis, and Gelatin Hydrolysis. Each test performed gives results such as motility, acid production, fermentation, carbon requirements, or detection of certain coenzymes. With a process of elimination, I determined which bacteria it was not and which bacterium I had, S. typhimurium. The expectation was to master the techniques for each test and utilize the results to determine the unknown bacterium I was given within a two-week period.

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.

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 I have been learned so far in the microbiology laboratory class for the identification of an unknown bacterium.

The Gram staining technique was developed by Hans Christian Gram in 1884 [1,15]. The catalase test is a simple, rapid, and accurate technique used to distinguish Gram-positive bacteria between catalase producers (Staphylococcus species) and catalase non-producers (Streptococcus species). The catalase tests accounts for the enzyme catalase, an enzyme used for the breakdown of hydrogen peroxide into oxygen and water. Generally strict anaerobes and aerotolerant anaerobes lack the enzyme catalase, whereas aerobes are easily associated with the production of catalase [12]. The third test used was the red blood cells (RBC) hemolysis test, which differentiates bacteria in three subcategories: α-hemolytic, β-hemolytic, and γ-hemolytic bacteria. For this test blood agar is used as a medium. Blood agar contains the fundamental nutrients for pathogens to grow (sheep blood composes 5% of the medium ingredients), and shows the results of blood breakdown. α-hemolysis is the partial breakdown of RBCs by microorganisms, β-hemolysis is the complete breakdown of RBCs, and γ-hemolysis is considered no breakdown of RBCs [2,10].

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.

After being assigned a broth containing two unknown bacteria on 3/17/15, I inoculated a sterilized wire loop with the bacteria and streaked it across a TSA plate. This was to separate the two bacteria. After two rounds of streaking, I discovered one of my bacteria was dead and had to acquire it separately from Dr. Christmann. Once my bacteria were separated, I began Gram staining. To Gram stain, I took a slide and spread each bacterium with a droplet of water onto two different slides.

This is a multipurpose media that allows to study three different characteristics of bacteria: sulfur reduction, indole production, and motility (SIM). These traits are very useful to identify gram-negative

Yersinia enterocolitica is an enteric pathogen with a wide range of clinical and immunological manifestations, which depend on the age and physical condition of the patient. Responsible for intestinal diseases, the most frequent occurrence in infants and children, including enterocolitis with an inflammatory diarrhea; however, in older children and young adults the symptoms include acute terminal ileitis and mesenteric lymphadenitis (mimicking appendicitis). On the other hand, in some cases, extraintestinal manifestations also could happen, and it’s including urinary tract and respiratory tract infection (empyema), osteoarticular infection (reactive arthritis), erythema nodosum, infected mycotic aneurysm, axillary abscesses, and

In the world of microbiology it is vitally important to be able to discern the identities of microorganisms. Not only is it important in a lab setting but as well as in healthcare in general. Properly identify what strain of bacteria a person has will aid in the proper medicine and dose given. Throughout the semester we have learned about different types of bacteria and certain test that can clearly identify them. The purpose of this lab report is to identify a Gram-positive or Gram-negative bacterium. Using all the knowledge of procedures and lab techniques identify the unknown and discuss all the tests you performed.

|EMB Agar | |Distinguishes bacteria that ferment |Dark blue colonies with|E. coli and P. |

The colonies were smooth, translucent, and had a white brownish color. The Gram stain resulted in Gram positive cocci. After the Gram stain was completed, the bacteria were streaked on a Mannitol-Salt Agar plate and a Catalase test was performed. After these test were completed a Phenol Red Dextrose Fermentation tube was inoculated, and a SIM Tube inoculated.

These obligate intracellular bacteria face challenges of not only needing to evade and survive the host immune response but also must use the resources of the host and be able to spread from one cell to next.

The Center of Disease Control stats that Yersinia Enterocolitica, also known as Y.enterocolitica is an infectious disease amongst humans that is deadly as well as a common disease that could spread throughout the world quickly through foods we consume and could also become deadly. The entirety of this research paper will include the casual agents, epidemiology, transmission, clinical features, diagnosis, and treatment, along with more in depth details will be discussed about this infectious disease. J. Pathog, the author of the Journal of Pathogens says the discovery of this disease was sixty years ago and was not known as a pathogen until1960 when it became a serious disease.

Another purpose of this experiment is to stress the importance of knowing the identity of a microorganism. Knowing the species of microorganism present in a sample provides a