Question

Determine how the following can be used for the diagnosis, prevention, or treatment of infectious disease: Prokaryotic ribosome DNA Cell wall Cell metabolism For example, prevention toward the cell membrane can occur through the use of soap (hand washing), but cannot be used to identify and diagnose. However, antibiotics such as Polymyxin B could be used against the cell membrane as a treatment. Select any infectious disease and determine how the four components listed above can be used for the diagnosis, prevention, and treatment of the disease. Be sure to describe current treatment trends by determining the class of drug that targets these cellular components and the mechanism in which they inhibit microbial replication/growth.

Answer 1

Let's consider the example of Tuberculosis (TB), caused by the bacterium Mycobacterium tuberculosis, and how the mentioned components can be used for diagnosis, prevention, and treatment:

1. Prokaryotic ribosome DNA:

- Diagnosis: Ribosomal DNA can be used for molecular diagnostics. Polymerase Chain Reaction (PCR) tests target specific regions of bacterial ribosomal DNA to identify the presence of Mycobacterium tuberculosis DNA in sputum or other samples.

- Prevention: Ribosomal DNA itself is not a target for prevention but can be used for strain identification to understand the epidemiology of TB outbreaks.

- Treatment: Antibiotics like Rifampicin and Rifabutin target the bacterial ribosome by inhibiting RNA synthesis, which is crucial for protein production in Mycobacterium tuberculosis.

2. Cell wall:

- Diagnosis: The unique mycolic acid composition in the cell wall of Mycobacterium tuberculosis is a key diagnostic feature. Acid-fast staining can help identify TB bacteria in sputum samples.

- Prevention: Preventing TB transmission includes strategies like isolation of infected individuals, vaccination with the Bacillus Calmette-Guérin (BCG) vaccine, and improving general public health to reduce TB incidence.

- Treatment: Drugs like Isoniazid and Ethambutol target components of the mycobacterial cell wall, disrupting its integrity and leading to cell death.

3. Cell metabolism:

- Diagnosis: Metabolic activity can be assessed through culture-based methods where Mycobacterium tuberculosis is grown in a specialized medium, and its growth is monitored.

- Prevention: Improved nutrition and living conditions can help reduce susceptibility to TB, but targeting cell metabolism directly is not a common prevention strategy.

- Treatment: Many TB drugs, including Pyrazinamide and Ethionamide, target the metabolic pathways of Mycobacterium tuberculosis, disrupting its ability to generate energy and replicate.

Current treatment trends for TB often involve combination therapy, as the bacterium can develop resistance to individual drugs. These drug combinations target multiple aspects of the bacterium's biology, such as its ribosomal DNA, cell wall, and metabolism, to effectively inhibit its growth and replication. This approach helps reduce the likelihood of drug resistance and is a key strategy in managing TB and other infectious diseases caused by bacteria.