P. aeroginosa Biofilms Exam Flashcards
Where do you find P aeroginosa?
The muscous mebrane in the lungs and other parts of the body
What sre the ozygen requirements of the P. Aeriginosa
Faculatative aerobic
What are the two serotypes of the flagella of P. Aeruginosa?
Serotype A and serotype B
What is doin with the flagella of P. aeroginosa?
- It has two serotypes
- immunogenic hook
- associated proteins
- When the flagella is lost, there is less chance of the host immune system ID-ing the P. aeruginosa.(Zhang et al 2007)
- Contact with cystic fibrosis fluids the flagella become down-regulated
- Function: cell-to-cell signalling, signal transduction
What are the fimbriae on the P aeroginosa?
Cup A-C gene cluster fimbriae Adherence factors
TYPE IV Pilus: mediates adhesion and translocation to epithelial cells allows an independent twitch movement independent of the flagella
Adhesion factors: colonisation factors and protective antigens
What does c-di-GMP do in P. aeruginosa?
makes the ole biofilms
What mobile genetic elements does P. aeruginosa have?
conjugative plasmid
Gene islands which are highly capable of horizontal gene transfer
What shape is the P. aeruginosa in the wild, aquatic, and lab
fingers
smol fingers
mushroom
What are the two pol;saccharides of the Alginate?
glumuronic acid and mannuroic acid
What is the seconds most common polysachharide produces in the EPS of the P. aeroginosa?
PSL: Polysacharide
repeating pentemer of mannose, phamnose, glucose
What population benifits from PSL: Polysacharide?
Thise who make it and have the genes
What can Paerogunosa bleb?
eDNA
How does P aeruginosa detach from the biofilm?
Aliginate lysase: algL
Rhampolipids: surficants
Cis-2-deconoic acids
DN-ase
What are the three Quorum sensing pathways of the P. aeruginosa?
LasI/LasR
RhlI/RhlR
Pseudomonas quinolone Signalling
What are the Proteins involved in the LasI/LasR Pathway?
c12-HSL
LasR
QscR
LasI
RhlR
What are the stages of the LasI/LasR quorum sensing pathways?
- C12-HSL binds to the receptor of the P. aeruginosa
- C12-HSL enters the cytoplasm of the P. aeruginosa
- LasR autoinducer complex binds to the promoter
- Upregulates Virulence factors: LasI
- LasI makes some C12-HSL: upregulates RhlR
What are the stages of the LasI/LasR quorum sensing pathways when you bind to QscR?
- C12-HSL binds to the receptor of the P. aeruginosa
- C12-HSL enters the cytoplasm of the P. aeruginosa
- C12-HSL binds to QscR in low cell density
- QcsR binds promoter to reduce Lasl/LasR and RhlI/RhlR operons
What virulence factors are upregulated by the LasI/LasR Quorum sensing pathway?
- LasI•Protease (lasA)
- Elastase (lasB)
- Exotoxin A (toxA)
- Alkaline phosphatase (aprA)
What proteins are involved in the RhlI/RhlR Quorum Sensing?
4-HSL
RhlR
RhIR
What are the stages of the RhlI/RhlR Quorum Sensing?
C4-HSL binds to the receptor of the P. aeruginosa
C12-HSL enters the cytoplasm of the P. aeruginosa
C4-HSL binds to RhlR creating the RhlR autoinducer complex
LasR autoinducer complex binds to the promoter.
Upregulates Virulence factors RhlI
RhlI makes some C4-HSL
What do all the three qurum sensing pathways of aerogunosa regulate?
Elastase production
What is the PQS involved in regulating?
maturation through releasing blebbed eDNA.
elastase production
What is the PQS system not in charge of regulating?
Not involved in sensing cell density
What proteins are involved in the Pseudomonas quinolone signal (PQS)
PQS
PQS-R
PQS-I
What are the stages of Pseudomonas quinolone signal (PQS)?
PQS binds to the receptor of the P. aeruginosa
PQS enters the cytoplasm of the P. aeruginosa
PQS binds to PQSR creating the LasR autoinducer complex
PQS-R autoinducer complex binds to the promoter.
Upregulates Virulence factors: PQSI
PQS-I makes some PQS
What virulence factors are involved with Pseudomonas quinolone signal (PQS)?
•Partially controls, depending on physiological states is required to work in tandem with the other systems…. the lasB elastase and the pyocyanin genes regulated•PQS-I
What are the virulence factors involved with RhlI/RhlR Quorum Sensing
•RhlI•rpoS – encodes stationary phase sigma factor•rhlAB – encodes rhamnosyltransferase (rhamnolipid production)•lecA – encodes a cytotoxic lectin•RhlI – autoregulatory feedback loop•Genes encoding pyocynain•Antibiotic•Oxides and reduces other molecules•lasB (elastase)•aprA (alkaline phosphatase)
