• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Isolation of a urea degrading bacteria.

Extracts from this document...


Michael Plit 3021034 Isolation of a Urea Degrading Bacteria Introduction Urea was the first organic chemical to be synthetically produced^1,^ previously it was thought that only living creatures could produce organic compounds Urea is naturally produced by the kidneys as waste from the degradation of amino acids. It is because of this that urea is commonly found in soils and is a useful nutrient source for bacteria that are able to utilise it, such as, Helicobacter pylori, Klebsiella pneumonia, all species of Proteus and Micrococcus luteus. These bacteria degrade urea in a reaction catalysed by the urease enzyme, CO(NH[2])[2 ]+ H[2]O �CO[2] + 2NH[3.] this process benefits the bacteria in several ways. The bacteria use the ammonia that is produced for respiration, the products also raise the pH of the environment. This promotes the growth of many urea degrading bacteria and inhibits competition from many other bacterial species. ...read more.


the chance of urea degrading bacteria being present was increased. * Culture in nutrient broth. This allowed all isolated microbes to grow. * Plate sample onto urea plates. On these plates urea was the only nutrient available, this meant that any bacteria that grew could degrade urea. * Perform urease test. Isolated bacteria are grown in a broth containing phosphate buffer, yeast extract, 2% urea and phenol red. An agar slope of the medium is heavily inoculated and incubated at 37^0c for at least four hours. If the organism only has low urease activity the phosphate buffer will neutralise the NH[3] produced. A red colour indicates that NH[3] has been produced and the result is positive^5.^ * Perform Gram stain. This is the most important stain in bacteriology and differentiates between gram positive and gram-negative cell walls, which indicates many things about cell structure, and taxonomy. ...read more.


luteus Results Test Result Urease Positive Gram Stain Positive Cocci Catalase Positive Motility Non-Motile Hugh and Leifson Obligate Aerobe These tests show that the isolated bacteria are Micrococcus able to degrade urea. Discussion The ability to degrade urea is no longer of great benefit to any species of Micrococcus although it remains a useful method of distinguishing M. luteus from other species. However, this is not the only test developed for this purpose. Before its revision based on 16s RNA, the Micrococcus genus contained nine species. M. luteus was separated from other species based on the following biochemical tests and their results^9. Test Result Citrate Negative Lactose Peptone Water Negative Glucose Peptone Water Negative Growth on 7% Na + NaCl Positive These tests are now redundant. If analysis of 16s RNA is not done, M. luteus can be distinguished on sight from other Micrococcus as it is now the only yellow species. References 1.smallfry.dmu.ac.uk/chem./mom/urea/urea.html 2. bergeys 2001 3. chinese Antarctic micrococcus 4 textbook 5.microbial methods pg 54 6.46 7.42 8.37 9.bergeys 1994 [1]http://www.britannica. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Living Things in their Environment section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Living Things in their Environment essays

  1. Using the streak plate method, compare the effect of two different brands of toothpaste ...

    This means that Colgate toothpaste will work better than the Sainsbury's own brand. METHOD: This method is exactly what I did and why I did what I did. The first thing to do was make sure that experiment was under aseptic conditions, this meant wiping down all the work surfaces with 'Milton', and washing hands at the start.

  2. Introduction to bacteria

    It is not dangerous to eat food containing bacteria. Certainly not, as long as they are the right kind of bugs. It may even be beneficial to eat dairy products with living cultures, although the evidence is still controversial. (Source: New York Times Science Q & A) ---.0 BIOLOGICAL WARFARE: Biological weapons are a unique class of weapons, living micro organisms.

  1. Respiration of yeast

    Therefore, if yeast is fungi, then it is an organism (living thing); thus yeast must respire to be alive, and that is why it is also used for baking because when it is added to a sugar solution, it converts the glucose into carbon dioxide and ethanol (which is toxic)

  2. cellular respiration

    Step 2: 150 mung beans placed onto styra foam tray which was layered with 4 layers of paper towel. The mung beans were watered down then another piece of wet paper towel was placed over the top. The water was then drained from the styra foam tray.

  1. The comparison of bacterial content in a range of milks.

    The optimum temperature for the bacteria to reproduce according to 'Gareth Williams Advanced Biology' the optimum temperature is between 20�c and 40�c. I will attempt to do this by keeping all the milk in a room that has a similar temperature daily (at 24�c).

  2. Can areas where accidental contamination with petroleum products be efficiently bioremediated and which bacteria ...

    Photograph-I and II shows the flasks of enrichment experiment The degradation of phenol was tested by using colorimetric method using 4-Aminoantipyrine and Potassium Ferricynide under alkaline condition. (reference-Standard methods for water and wastewater analysis APHA- American public health association publications).

  1. Investigating the effect of four antibiotic agents on gram positive and gram negative bacteria.

    Both types of bacteria contain peptidoglycan in the cell wall, but in gram-negative bacteria, various other layers protect it, including a more complex outer membrane and so the stain cannot reach it to cause the colouration. Below is a picture of Escherichia coli after it has been gram-stained.

  2. The main aim in the life science lessons is to learn how to handle ...

    In order to study more about bacteria, we will collect samples, which are suspected to contain bacteria and culture it on LB agar. We will also test for the bacteria on our thumb before and after washing of hands. Thereafter, to observe the bacteria more closely and clearly, we will

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work