What are an examples of unculturable bacteria?

Steps for Koch's postulate:

1. Association of the putative

causative agent with the

lesions of the disease

2. Isolation of the agent in pure

culture

3. Demonstration of the disease

upon introduction of the pure

culture of the agent into the

host

4. Re-isolation of the agent from

the infected or diseased host

Limitations:

Colonization with no

symptoms

• Non-culturable bacterias

• No disease models;

disease too serious to use

in human volunteers

Given the steps to Koch's postulate and the limitiations provided below it, how does antimicrobial drugs overcome these limitations?

Imagine yourself as a clinical microbiologist with all ofthe
diagnostic tools described in this chapter available for your
analyses. Which tool(s) would you use (and why) if (1) A
patient had a life-threatening infection caused by adifficultto-
culture bacterium and where treatment of the infection
was absolutely dependent on an extremely rapid identification
of the pathogen? (2) A patient had a less severe
bacterial infection where the pathogen was easily culturable
and treatable?

refer to an example of positive regulation of gene expression to demonstrate how bacteria live on culture plants, what example would you chose? explain why