Question

0-57 Sat 25. May UOPEOPLE TERM 4 25. May 2019 at 10:53 Let's see if when we describe the characteristics of microorganisms completely your colleagues will provide more accurate answers of what pathogen that is! 1. Choose a pathogen that can invade the human body and research it in depth. Describe as many characteristics of the microscopic structure as possible, using size, shape (such as coccus), staining characteristics (such as Gram stain), or any detail other than its name. Include the transmission, etiology, and host of the disease. 2. Try to provide a written "picture" in another person's minds without directly giving away the answer 3. Your description must be complete enough to rule out any other answers and avoid confusion (check your work by researching your organism's characteristics before posting to be sure you could answer it yourself!),

Answer 1

Mycobacterium tuberculosis

• Discovered by Robert Koch
• Human bacterial pathogen.
• It’s a causative agent of tuberculosis in humans

General microbiological aspects about Mycobacterium tuberculosis

• It’s a non-motile obligate aerobic bacteria
• Shape and size: small bacilli (2-4 µm in length)
• Non-spore forming
• Slow growing

Staining characteristics:

Mycobacterium tuberculosis may appears gram negative or gram positive on gram straining. The cell surface of Mycobacterium tuberculosis has a waxy coating of mycolic acid. The presence of this waxy coating on the surface does not allow gram stain to pass or mycolic acid inhibits the absorption of gram stain by the cell wall, therefore gram staining could not work in case of Mycobacterium tuberculosis

Acid-fast stains such as Ziehl-Neelsen has been used to identify the Mycobacterium tuberculosis

Infection and Transmission

Tuberculosis is widely transmitted by the inhalation of aerosols containing the bacilli of Mycobacterium tuberculosis. Additionally, the Mycobacterium tuberculosis get easily transmitted through air droplets of a person having tuberculosis. Coughing, sneezing, speaking, or singing may transmits the air droplet originating from the infected person to the healthy person.

The initial infection of the Mycobacterium tuberculosis may be mild, however, if left untreated, the Mycobacterium tuberculosis could infect alveoli of respiratory system and multiply in alveolar macrophages

.