Lec. 23: Biofilms Flashcards
Most bacteria in nature live in ______ communities.
biofilm
What is the genus name of the pathogen that causes Legionnaire’s Disease?
Legionella
Legionella
- found in wet areas, especially hot tubs or areas with warm temperatures
- like human body temperature
- enters the body by inhalation
- form biofilms so can only be found in the area is swabbed not only in water samples
Biofilm Case Study Outcomes
- disease: Legionnaire’s Disease
- pathogen: Legionella
- experiment: control, chlorine, heat+chlorine, ozonation, & ozonation+chlorine
- results: combo treatments are best; choose most cost-effective treatment
Major Characteristics of Biofilms
- dynamic and responsive to their environment
- show aspects of both solids and liquids (viscoelastic)
- can coordinate behavior via intercellular “communication” using biochemical signaling molecules
- less susceptible to antimicrobial agents
In the ship scenario, which sample was positive for Legionella after swabbing?
Hot tub
In the ship scenario, which treatment would you recommend that they use in the future?
Ozone + Chlorine
Water samples were brought to your lab where you observed them under a _________ microscope using the ___________ , using a tagged antibody specific to Legionella.
fluorescence; Direct Fluorescence Antibody Assay
You viewed a control sample (from a ________ of Legionella)
pure culture
You ask the CDC to go back and _____ the surfaces instead of just taking water samples.
swab
What is the lifestyle of Legionella?
It grows in soil, fresh water, hot tubs as a luxuriant biofilm. It survives temperatures of 0-63C and does best at 98.6F.
Why is Legionella such a problem on cruise ships?
It causes pneumnia-like disease.
Which of the WATER samples were positive for the Legionella pathogenic group?
The one with the biofilm, which was yellow in color. (These were in the hot tub)
Did the positive samples with Legionella look different from the control?
Yes because the antibodies attached to it even when the excess is washed off.
