Unknown Organism Report: NWTC Microbiology

There are many reasons for identifying an unknown bacterium. The reasons range from medical purposes, such as determining if the unknown could cause ailments in living things or knowing what microorganisms are needed to make antibiotics. The experiment was done by applying methods in order to identify an unknown bacterium.

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.

In order to diagnose this patient with this bacterium, I would place an order for a blood culture. Blood cultures are indicated in patients with sepsis, severe skin and soft tissue infections, or unstable vital signs; example massive organ failure. Blood cultures

The Unknown Bacteria 36/Bacteria # 2 on a TSA plate was examined by the naked eye and under a dissecting microscope. Bacteria # 2 was approximately 3 - 4 mm in diameter. They were circular in form with an entire margin and a flat elevation. The colonies were rough (granular), translucent, and white brownish color with black granules. The Gram stain resulted in a Gram negative rod. After the Gram stain was completed, the bacteria were streaked on an Eosin -Methylene Blue Agar plate and an Enterotube II was inoculated.

Next I performed a KOH test to further confirm that my organism was a Gram-negative species. For the KOH test, I added 3 drops of 10% potassium hydroxide (KOH) to a small drop of distilled water onto a clean microscope slide, transferred a visible clump of organism to the KOH solution using my inoculating loop. I than mixed the cells into the solution using small, circular motions for 60 seconds and then lifted up the loop to look for what appears to be a “stringing” affect which means it’s confirmed that it is gram- negative species. Next, I created a streak plate using nutrient agar so that I could see pure culture of my organism. I aseptically obtained a loop full of my organism and gently inoculated one quarter of the nutrient agar plate by running the loop back and forth across the surface. I then flame sterilized the inoculating loop, allowing it to cool for 10 seconds, and then streaked the organism from quadrant I into quadrant II using a zigzag motion technique. I repeated those steps streaking from quadrant II to quadrant III and then streaking from quadrant III to quadrant IV. Once completed, I put the streak plate in the incubator at 37° for 24-48 hours. 48 hours later, I check my streak plate and it had a lot of growth on it. I was able to determine that the organism was definitely an off white color, opaque. The IV quadrant was the quadrant that best

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.

rarely, can spread through the blood stream and infect the joints, heart valves, or the brain. The

Citrobacter Freundii is a species of bacteria that can be potentially harmful to humans. It is known to cause meningitis by protruding into the brain and replicating itself (1). The Citrobacter species has also been found as a cause of some urinary tract infections, diarrhea, and even gastrointestinal diseases and symptoms (3). C. Freundii can be located in a wide variety of soils and water (3). Lastly, it is also the cause of many nosocomial infections due to its presence in water (1).

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.

I discovered that my unknown organism was Serratia marcescens. This organism is gram negative and bacillus shaped. It is a member of the Enertobacteriae family. This organism appears a red blood like color when it grows on media. It is anaerobic, but can also survive under aerobic conditions. There are some strains of Serratia marcescens that are motile and have flagellum. It is able to produce the enzymes chitinase, lipase, protease, nuclease, and serrawttin. It is a non-endospore forming bacteria, chromogenic, and does not ferment lactose. (Falkiner, 1997)

|a chief complaint (from family) of worsening of |by the presence of a bacterial or viral infection. Febrile |secondary to CVA |

It is critical to perform other tests to confirm previous results even if all the steps were performed correctly. Once the unknown bacteria grew on nutrient agar, I observed convex, undulated, punctiform, creamy, off-white colonies that

Unknown mixed microorganisms were collected from a building sample, air and fingerprints. The sample microorganisms were swabbed onto petri dishes that contained growth mediums: Vancomycin, EMB- lactose and PEA. They were placed in an incubator at 37º C for 1-2 days to allow growth on the mediums. The incubated microorganisms were observed to determine whether the samples were bacteria or fungi. The samples that had the bacterial colony morphology were selected for the study.

It is believed that the virus or bacteria has changed the chemical make-up of the cells of the nervous system (NINDS, 2011). This activates the body’s immune response because it views the cells of the nervous system as a foreign object in the body. About 60% of cases of GBS follow an infection of the lungs or digestive system (Mayo Clinic, 2011). There are many types of viruses that scientist believe trigger GBS, these include: campylobacter jejuni, mycoplasma, cytomegalovirus, Epstein-barr virus, or the varicella- zoster virus (Web MD, 2011). Campylobacter jejuni is a type of virus that can cause food poisoning, mycoplasma can cause pneumonia, and Epstein- barr virus can cause mononucleosis. Varicella- zoster virus is typically the cause of chicken pox and shingles and the cytomegalovirus causes flu like symptoms (Web MD, 2011). It is unclear why this happens in some people and not in others, or why some cases of Guillain- Barre have no known trigger.

The cause of GBS is not clear, nonetheless it is believed to be triggered by an acute infectious process. Infections can be viral or bacterial infections. Such as, Campylobacter jejuni, cytomegalovirus, mononucleosis, parainfluenza 2, measles, mumps, hepatitis A and B viruses (Des Jardin and Burton 2016).