Lab Report : Pseudomonas Aeruginosa

There are many differents ways to identify a bacterial unknown and many different situations where identification would be beneficial. One way to identify bacterial unknowns is to perform biochemical tests. In this experiment multiple biochemical tests were done, by performing these tests on the bacterial unknown received the two different bacteria were then identified. The citrate test is done to test the ability of organisms to use citrate as a carbon source. This test uses Simmons citrate agar, the agar contains sodium citrate as the only carbon source and has bromothymol blue as the pH indicator. The organisms that use citrate as a carbon source use the enzyme to transport the citrate into the cell. The cells converts ammonium dihydrogen

Unlike many environmental bacteria, Pseudomonas aeruginosa has a remarkable capacity to cause disease in susceptible hosts. It has the ability to adapt to and thrive in many ecological niches, from water and soil to plant and animal tissues. The bacterium is capable of utilizing a wide range of organic compounds as food sources, thus giving it an exceptional ability to

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.

The three organisms that were identified in my unknown tube were Citrobacter freundii, Corynebacterium xerosis, and Micrococcus. The first step of this project involved isolating the three organisms that were within the mixed culture. Once I successfully isolated them, I was able to do specific colony morphologies for each of the organisms. The characteristics of Citrobacter freundii includes butyrous, opaque, circular, convex, and beige. Corynebacterium xerosis is white, small, punctiform, circular, dry, and brittle. Micrococcus is white, large, opaque, butyrous and circular.

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

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 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.

The thioglycollate broth showed that Clostridium sporogenes, Escherichia coli, Micrococcus luteus, and Enterococcus faecalis all showed growth that was throughout the tube but there was a slight inhibition of growth at the very top of the tube. Pseudomonas aeruginosa showed growth throughout all of the tube including the very top of the tube. With the TSA + glucose plate, all the bacteria but C. sporogenes was able to grow on the plate aerobically. For the plates that were grown in anaerobic conditions, only C. sporogenes, E. coli, and E. faecalis were able to grow on the plates.

The number of bacteria (CFU/ml) in each serum and saline sample will be Serratia in serum, Pseudomonas in serum, Serratia in saline, and Pseudomonas in saline. We will count if it is 30-300 colonies which it shows me that there is 92, 65, 293, and 150. In Serratia in serum, it is 9.2 x 10^2 CFU/ml. In Pseudomonas in serum, it is 6.5 x 10^7 CFC/ml. In Serratia in saline, it is 2.93 x 10^8 CFU/ml. In Pseudomonas in saline, it is 1.50 x 10^8 CFU/ml.

Pseudomonas Aeruginosa is a bacteria often found in the environment. It is the most common nosocomial infection affecting people with weak immune systems. Pseudomonas infections are usually spread by medical equipment which are not properly cleaned and by the hands of the medical workers. It can be prevented by washing your hands correctly and by conducting environment screening. They are typically treated with antibiotics. However, they are becoming multi-drug resistant.

Pseudomonas aeruginosa (P. aeruginosa) is an important Gram-negative opportunistic pathogen that has the capability to create variable clinical infections including, but not limited to, wound infections, urinary tract infections (UTIs) and blood stream infections (BSI), particularly in hospitalized and immunocompromised patients (1, 2). P. aeruginosa was the second most common cause of hospital-acquired pneumonia, third and fifth common cause of hospital-acquired UTIs in USA and Europe, respectively (2- 4). It has been demonstrated that P. aeruginosa due to low permeability of outer membrane in combination with efflux pump overexpression is intrinsically resistant to a variety of antibiotics (5). Expression of Different classes of extended-spectrum

Pseudomonas aeruginosa is a clinically significant opportunistic pathogen that infects compromised hosts in hospitals. This organism has an outer membrane with a low level of permeability and is thereby intrinsically resistant to a wide variety of commonly used antibiotics. Only a few antimicrobial agents, such as carbapenems and quinolones, show potent antibacterial activity against this species. In recent years, a number of clinical P. aeruginosa isolates have been reported to be resistant to some of these antibiotics, especially quinolones (Masuda et al.,

The genus Pseudomonas is the most heterogenous and ecologically significant group of known bacteria, and includes Gram-negative motile aerobic rods belonging to the bacterial family Pseudomonadaceae which includes other genera that are wide-spread throughout nature and characterized by elevated metabolic versatility the nutritional requirements of Pseudomonas spp. are very simple, and the genus is found in natural habitats like soil, fresh water, marine environments etc., but it has also been isolated from clinical instruments, aseptic solutions, cosmetics and medical products (152, 30) Pseudomonas species are measuring 0.5 to 0.8, μm by 1.5 to 3.0 μm. Species are distinguished by several tests like biochemical and DNA hybridization

Pseudomonas aeruginosa is an opportunistic pathogen which infects virtually all tissues, can also infect immune-compromised individuals and involved in hospital acquired infections . Burn patients, mechanically ventilated patients, and cystic fibrosis (CF) patients are more vulnerable to P. aeruginosa infections. It is responsible for morbidity and mortality in patients with cystic fibrosis . P. aeruginosa infections in hospitals are widely spread in intensive care units and those patients having catheterization, burn, and/or chronic illnesses. This bacterial species contain a variety of virulence factors that contribute to its pathogenicity. It also has other virulence factors such as exotoxin A, exoenzyme S, and lipopolysaccharide (LPS)

Each mixed culture that was tested had one gram positive and one gram negative bacterial species. The possible species of bacteria that could have been isolated from the mixtures included the following: Bacillus subtilis, Corynebacterium glutamicum, Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, Enterobacter aerogenes, Salmonella enterica, and Pseudomonas aeruginosa. The identities of the unknown species were determined through comparing the experimental data against data acquired from earlier experimentation.