Lab Report On Enteric Bacteria

This report discusses the procedures and equipment needed to determine a bacterium knowing and having nothing but the sample bacteria given by the instructor. The importance of this lab is to test your ability to think clearly about what each test will tell you about your unknown organism and selecting tests that will save time and give you the most information. The objective of this lab is to determine what species level and genus level your bacterium is categorized as. The first step taken to determine the bacteria was to do a sub-culture of my stock broth to have a backup of my bacteria just in case my broth became contaminated. Doing a T-streak on a TSA plate is when the plate is divided into three sections and using an inoculating loop, grab some

Escherichia coli are rod shaped, gram negative bacteria often found in the gut of humans and other warm-blooded mammals (Jacques & Ngo, 2004). It is transmitted primarily through faecal contaminated food and water. Most strains of E. coli are not harmful to humans, however some strains are pathogenic and can cause symptoms including diarrhoea (Unknown, 2012).

While conducting this experiment many questions came to mind what effect can plasmids had on the transformation of E. coli and why did CaCl2 had to be used. During the experiment the solution was used to neutralized negative charges and heat sock was done to traumatize the cell membrane to get the cell ready for the intake of plasmids. As shown above observation can be made from the agar plate which describes the affect that plasmid had on the each. First, with the LB c, LB np and LB lux DNA exhibited lawn growth consequently lux brought about the bioluminescence effect on plates LB lux. This was the result of the absence of the Ampicillin antibiotic and the lux together. So, agar plates labeled LB/AMP c and LB/AMP lux, shown colonial growth which is a clear indication that minimal

E. coli are usually harmless, but can cause urinary tract infections, respiratory illnesses and other illnesses. This bacterium is also beneficial to humans and are part of our natural intestinal microflora, but E. coli can also lead to mild to serious illnesses in the human body. Disease causing E. coli are grouped according to the ways they cause illnesses. Escherichia coli is spread when people consume at-risk foods, these include foods such as undercooked ground beef, produce that have come into contact with fecal matter, contaminated water and unpasteurized dairy and juice products. This bacterium can also spread from person to person by unwashed hands, contaminated surfaces (fomites) and pond water.

Enterobacter aerogenes is a Gram-negative, rod shaped bacteria, from the Genus Enterobacter. Several experiments were performed to properly indicate the bacteria, such as the citrate utilization test, motility test, and glucose fermentation test. All of which tested positive. The purpose of these multiple tests was to become familiar with the process of testing, the different types of tests, and how to identify positive and negative results to properly conclude and identify the correct bacteria Genus and species.

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).

Esherichia coli also known as E. coli is a bacterium that lives in your gut. (1). it was founded by Theodore von Esherich in 1888. There are many people that can get the bacteria. Also there are thousands of strands of E.coli. Six E. coli O157 outbreaks were identified during 2007. Four of the outbreaks involved foodborne transmission. (Eshericha Coli). Six Minnesota cases and one Wisconsin case with the same or closely-related PFGE subtype of E. coli O157:H7, and an additional Minnesota case of Shiga-toxin producing E. coli that was not culture-confirmed, attended the Minnesota State Fair in August. All but one of the cases showed cattle or visited the cattle

The lack of oversight in waste management and sanitation has led to the contamination of the food supply. According to the American Society for the Prevention of Cruelty to Animals, “Farms that are not properly maintained can be breeding grounds for salmonella and E. coli, which are passed to humans through meat, dairy and eggs” (ASPCA). Reviewed by Dr. Jennifer Robinson, salmonella and E. coli are types of bacterial diseases that affect the intestinal tract and some symptoms include diarrhea, fever and abdominal cramps (WebMD). This can be a serious food poisoning problem because if not treated wisely people who are exposed are at risk with dying. Each year 76 million Americans become sick from food borne illness and thousands of people die according to the ASPCA.

In this lab experiment, students had to create a growth curve for E. coli. The E. coli growth curve would illustrate the progression of the population of E. coli a set time period. In this case, the growth curve depicted the population of E. coli over a 12-hour period. The growth curve for E. coli was created from the absorbance levels, the optical density(OD), recorded from the spectrophotometer.

Enterococcus faecium is an ESKAPE pathogen that is one of the leading causes of nosocomial infections not only in the United States of America, but throughout the world. ESKAPE pathogens in general are problematic because they are antibiotic resistant to many of the drugs that are available, therefore making them one of the greatest challenges that clinical practice settings experience today

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.

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.

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.

Infectious bacterial diarrhea is a common occurrence among the elderly people, children, and the immunocompromised individuals. One of the major reasons behind the infectious diarrhea is the inflammation of the colon. Colitis is the inflammation of the colon resulting to symptoms such as diarrhea, tenesmus, fever, and severe abdominal pain. The common pathologic organisms responsible for the infection include Camphylobacter, Shigella, Salmonella, Escherichia, and the Yersinia species (Papaconstantinou, & Thomas, 2007). The initial infection of Camphylobacter, C, fetus, was discovered and described in 1947 after several cases appeared and it was isolated from blood (Loss, Mangla, & Pereira, 1980). Later, the discovery of new identification techniques led to the isolation of other strains of the species. Currently, the identification has developed, leading to isolation of bacteria such as Camphylobacter and E. coli in culture techniques and other isolation techniques. Treatment of this disease uses multidisciplinary approach of both antibiotics and supportive therapy.

Escherichia coli are commonly found in lower intestine of warm blooded animals. Most E. coli are harmless. The bacteria can be grown easily and its genetics are relatively simple and easy to study, making it the best-studied prokaryotic organism. Certain strains of E. coli can produce toxins that can cause food poisoning when eating unwashed vegetables. (Wikipedia, 2010)