Kim Lewis PhD

"Uncultivable Organisms and Bacterial Persistence"

2:00 pm

Saturday, January 21, 2012

International Academy of Endodontics, Annual Meeting

The Fairmont Hotel

Dallas, Texas

Northeastern University, Boston, USA

Microorganisms produce persisters – dormant variants of regular cells that are largely responsible for drug tolerance of chronic infections. Stochastic expression of toxin/antitoxin genes causes inhibition of important cellular functions such as protein synthesis and energy production, sending a small part of the population into a dormant state. Dormancy is also the default mode of life for most microorganisms both in the natural environment and in the human microbiome. Most of the species require a growth factor and do not grow on conventional nutrient medium in the lab. For many uncultured environmental bacteria, iron chelating siderophores produced by their neighbors act as an essential growth factor. Uncultured bacteria of the oral cavity similarly depend on their neighbors, and we recently identified the first class of growth factors for these organisms.

DRUG TOLERANT AND UNCULTURED MICROORGANISMS: A CASE STUDY OF DORMANCY

Learning objectives:

1. The participants will learn about the nature of drug tolerance and its mechanistic distinction from drug resistance.

2. The participants will learn about the mechanism of formation of persister cells responsible for biofilm drug tolerance.

3. The participants will learn about the mechanism underlying bacterial uncultivability.

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