S. aureus Biofilms Exam Flashcards
Where do you get infected with S. aureus?
upper respiratory asn skin
What are the O2 requirements for S. aureus?
aerobic
What is the medical relevance of S. aeureus?
clogs the tubes of medical devices and antibiotic resistance
What is the major polysacharide inthe aureus EPS?
PNAG
What breaks down the S. aureus biofilm?
DN-ase
Glycoside hydrolase dispirsin B
What do you find in the biofilm EPS of Aureus?
Blebbed eDNA
RNA : Chiba et al
Blood RNA more biofilm formation
NAG
What cell surface adhesion factors are there in S. aureus?
Clumping factor: CLFA&B Surface Associated Proteins: SdrC,D,&E Collagen Adhesion: cna Fibronectin Binding Proteins: FnbpA&B Bone sialo-binding protein: Bbp S. aureus surface protein: AsaG&C Autolysin: AtlA&E Wallteichoic acid/lipteichoic acid Biofilm associated proteins: bap Iron regulated surface determinants: IsadA, B, C, & H
What protein is responsible for sorting the outercell wall proteins of aureus?
Sortase A
What do the phenol soluble modulins do?
They stabalise the biofilms through production of amyloids but they reduce the size of the biofilms
What results in the dispersil of the S. aureus biofilms?
Nuc 1 &2 (Forson et al. 20202)
Dispirsin B
RN-ase
Glycoside hydrolase dispirsin B
What toxins does the S. aureus produce?
Beta toxins
What is an Eap?
Extracellular adherence protein
What are the four receptors that S. aureus will adhere to?
Fibronectin
Fibrigen
Collogen
cytokeratin
What are the stages of the Agr (Accessory Gene Regulator) Quorum Sensing? for Promoter 2?
AIP binds to the Agrc trans membrane protein
AgrC phosphorylates AgrA
AgrA binds to the PR Promoter: upregulating AgrA,C,B,&B
The AgrD propetide is transported out of the cell by AgrB: During export the AgrD is modified to AIP
AIP (Autoinducer peptide) then continues the cycle
What are the stages of the Agr (Accessory Gene Regulator) Quorum Sensing? for Promoter 3?
phosphorylated AgrA binds to promoter P3 and RNA III is transcribed
Which creates many virulence factors
