Nasal passageway

From MicrobeWiki, the student-edited microbiology resource

Template:Nasal Passageway

Description of Nasal Passageway

Location of the Nasal Passageway

The main entry to the nasal passageway is through the nostrils, inside the nose, which is located on the face.

The walls of the nasal passages are coated with respiratory mucous membranes which contain innumerable tiny hair-like cells that act to move waves of mucus toward the throat. Dust, bacteria, and other particles inhaled from the air are trapped by the mucus in the nose, carried back, swallowed and dropped into the gastric juices to nullify any potential harm they might do. The mucus contains lysozyme that dissolves and kills the bacteria, but most bacteria are not killed by it.

Physical Conditions?

What are the conditions in your niche? Temperature, pressure, pH, moisture, etc. Normal: The temperature of the normal passageway should be around 31 degrees Celcius. The pressure of the normal passageway should be around 1 atm.

Influence by Adjacent Communities (if any)

Is your niche close to another niche or influenced by another community of organisms? Throat, Stomach, Lungs, Skin...

Conditions under which the environment changes

Do any of the physical conditions change? Are there chemicals, other organisms, nutrients, etc. that might change the community of your niche.

Anything that might irritate a human's nose, like air pollution, smoke, pesticides, etc., may cause swelling and blockage of the nasal passageways which will lead to bacterial growth and infection. The trapped mucus within the nasal will create a breeding ground for bacteria.

Who lives in the Nasal Passageway?

Which microbes are present?

You may refer to organisms by genus or by genus and species, depending upon how detailed the your information might be. If there is already a microbewiki page describing that organism, make a link to it.

Staphylococcus epidermidis with Corynebacteria predominantly colonizes the upper respiratory tract, especially the nostrils. S. epidermidis covers 90%-100% staphylococci from the nasal cavity when S. aureus is not present.

Corynebacterium is a Gram-positive normal flora in the nose. Most species of Corynebacterium will not cause diseases in humans; however, there is a specific speicies that is highly infectious. The Corynebacterium diptheriae, causes infects the upper respiratory tract, and can be deadly if untreated.

Another Gram-positive bacterium that lives in the human nose is the Staphylococcus aureus, often referred to as staph. It is carried either on the skin or in the nose of healthy people, but 25% - 30% of the population is populated in the nose. Well Staph is growing, it will not cause any infection, until the bacteria can enter a wound.

Are there any other non-microbes present?

Plants? Animals? Fungi? etc. Normal: Hopefully, no plants, animals, or fungi live in the nasal passageway.

Do the microbes that are present interact with each other?

Describe any negative (competition) or positive (symbiosis) behavior

The reason only 25% - 30% of the nasal passageway is populated by the Staph. aureus is beacuse Staph. epidermidis and Corynebacterium have a negative symbiosis behavior with the Staph. aureus. Some possible reasons for the decrease in Staph. aureus may be the synthesis of bactericidal exoprotiens by the Staph. epidermidis or the competition of specific attachment to epithelial cells, which Corynebacterium has a higher affinity for mucus than Staph. aureus. Although Stap. epidermidis has a negative impact on Staph. aureus, Staph. aureus has a higher affinity for mucus than does Staph. epidermidis.

Do the microbes change their environment?

Do they alter pH, attach to surfaces, secrete anything, etc. etc.

Do the microbes carry out any metabolism that affects their environment?

Do they ferment sugars to produce acid, break down large molecules, fix nitrogen, etc. etc.

Current Research

Enter summaries of the most recent research. You may find it more appropriate to include this as a subsection under several of your other sections rather than separately here at the end. You should include at least FOUR topics of research and summarize each in terms of the question being asked, the results so far, and the topics for future study. (more will be expected from larger groups than from smaller groups)

As previously mentioned, Staphylococcus aureus is commonly found in the nose. Researchers from the University of Washington were interested in finding out why this bacterium is able to survive the human's natural production of nitric oxide in the nasal passages. This production of nitric oxide in the nose and nasal passages usually protects against disease causing bacteria by preventing their respiration process. These researchers found out that Staph aureus produces lactic acid in the presence of nitric oxide,making a chemical balance, allowing it to continue to grow in this type of environment. The researchers then found a way to remove the lactic acid production by Staphylococcus aureus and found that it was then not able to survive in the presence of nitric oxide. This was tested in mice and the researchers also found that there were no diseases caused by the modified bacterium. The researchers hope to use this type of modification to find new ways to prevent the survival of such bacteria without the use of antibiotics.

(Not sure if this is an ok summary for current research, let me know if I should find something else or try to add more to it.- Naty)

References

[Sample reference] Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "Palaeococcus ferrophilus gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". International Journal of Systematic and Evolutionary Microbiology. 2000. Volume 50. p. 489-500.

Lina, G., Boutite, F., Tristan, A., Bes, M., Etienne, J., Vandenesch, F., "Bacterial Competition for Human Nasal Cavity Colonization: Role of Staphylococcal agr Alleles". "Applied and Environmental Microbiology". 2003. Vol. 69. No. 1. p. 18-23.

Edited by Jacinda Chen , Wayne Chen , Josephe Dalidi , Jennifer Hao , Rutu Kothari , Nidhi Patel , Natividad Rodriguez , Prudencio Sy, students of Rachel Larsen