Draw a diagram or take a picture if that helps. Streptococci and streptobacilli form chains. Upon reviewing the identification tables, the deciding biochemical test was the Casein test which tests for the production of the enzyme casease to break down the milk protein casein. More complex organisms, including all plants and animals, whose cells have. Zinc powder act as a catalyst and that will favours the reduction of nitrate to nitrite. 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. Then, a Nitrate broth test was performed.
It's a gentle stain that doesn't require heat-fixing and thus doesn't distort bacteria. There are also bacteria that are facultative anaerobes, meaning that in presence of oxygen, they will use it but if they find themselves in anaerobic conditions, they'll be able to grow using fermentation pathways or anaerobic respiration. Twenty percent of the human population are carriers of S aureus, which can be found on the skin and inside the nasal passages. 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. More Rose like to me. To decipher between which biochemical tests to perform, the gram positive and negative tables handed out by the Professor, were referred to.
The first round of streak plating was not effective and another streak plate was completed and inoculated again for 120 hours before investigation. The unknown is gram - bacteria. It can cause many illnesses, from minor skin infections, to life threatening diseases such as meningitis, pneumonia, osteomyelitis, endocarditis, toxic shock syndrome, and sepsis Todar, 2012. That's pretty much a general scheme for common bacterial genera. For example, the first two streak plates made were ineffective at separating the two unknowns from each other.
In order to do the streak method, an inoculating loop was sterilized with a Bunsen burner and put into the unknown specimen. Catalase has one of the highest turnover numbers of all enzymes such that one molecule of catalase can convert millions of molecules of hydrogen peroxide to water and oxygen in a second. 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. We will also determine if the bacteria is stable or non-stable acid fermenters. Staining Reactions: Staining is a simple basic technique that is used to identify microorganisms. Rigid, spiral-shaped bacteria are known as spirilla and are only gram-negative. Lab Manual for General Microbiology: Bio 203.
Medicago truncatula Genotype seed line Soil Sample Average Number of Nodules Average Dry Plant Biomass A17 Salses Soil France 21 0. Broth 37 C Cluster of bacteria on the bottom which is rose in color. A list of possible organisms was given before any tests were run and a chart with the accepted test results for each organism was given as well. In the absence of these enzymes, the toxic concentration of H 2O 2 cannot be degraded when these organisms are cultivated in the presence of oxygen. If you're stumped, you're likely missing something in your materials. The next step to determining which bacteria you have is to know if it's aerobic or anaerobic. I usually go in and wing it hoping for a result that will support my hypothesis.
Sodium citrate is one of the important metabolite of Kreb's cycle. In order to do this, a nutrient agar plate was used. This could cause painful infections such as urinary tract infections 3. The antisera for different bacteria are commercially available. Each of the tests performed provided some key information about the bacteria in question and how it functions. Learning time This project was conducted over six weeks.
Coagulase Test: Coagulases are enzymes that clot blood plasma by a mechanism that is similar to normal clotting. If you streak for isolated colonies you can make new broth solutions each containing only a single species. Week 5: Identity verification tests and design of an experiment to learn about the biology of rhizobia During this week the students carried out the identity verification experiments proposed during the previous week. The flow charts on the following page list these tests and results for the Gram positive and Gram negative bacteria. The slide was viewed on an oil immersion 100x. Through the process of elimination, I concluded that my sample must have been Micrococcus Luteus.
Cells are treated first with carbol fushin which is heat-fixed, then with acid alcohol which decoulorize all cells except acid fast bacteria and finally with a counterstain methylene blue. These bacteria must be able to be identified in order to treat patients properly, efficiently and safely. The acid fast stain differentiates bacterial cells with lipoidal cell call. It is an indication of pathogenicity since if a bacteria can coagulate the blood, it can wall off from the immune system. All of the following tests were performed on this unknown on February 09, 2008. That's somewhat time consuming though and could take several days. The Unknown bacteria is Enterobacter aerogenes B.