Lecture 8 Flashcards
What happens if the receptor (LuxR) of the lux operon is not functional but the light and signal genes are functional?
If the receptor molecule does not work then quorum sensing ability is disabled/does not work
-cells will NOT GLOW
What happens if the receptor molecule and light genes are functional but the signal genes are not functional
Without signaling molecules, quorum sensing does not take place
-the cells will NOT GLOW
What will happen if one mutant strain that has a non functional receptor and functional light and signal genes is plated with a strain that has a functional receptor and light genes but not functional signal genes
The signal genes from A will diffuse to side B and since B has a functional receptor it will emit light, A will not emit light
What are the benefits for the squid having A. fisherii inside its guts
When the squid glows from the bacteria it is similar to moonlight’s reflection on the water’s surface which helps it camouflage and hide from big fish
What are the benefits to A.fisherii inside the squid’s gut?
Bacteria gets food and shelter from the squid
Why do cell wait for a quorum?
It would be too costly if only 1 cell did (ex glow), it is advantageous if many cells participate, so it should wait until there is a high concentration
Why do organisms who don’t live in symbiosis with squid emit light?
-Mating
-Attract prey
-scare prey
-DNA repair
What are biofilms?
organized communities of microorganisms that adhere to surfaces and are surrounded by a matrix of extracellular polymeric substances (EPS)
How do bacteria break biofilms
Enzymes
What are biofilm structure?
Exopolysaccharide matrix, lipid proteins, eDNA
What is eDNA?
Extracellular DNA
-6x more abundant than proteins and 18x more abundant than carbohydrates
How to test whether eDNA maintains biofilm structure or not in a lab?
Use DNase since it disrupts biofilm formation
-works well in early stages
