Biofilms Flashcards
Define biofilm
Syntrophic community of microorganisms which adhere to one another and often also to a surface
What are the two states of bacteria
Mobile planktonic and static biofilms
Biofilms contain what 4 substances (E,E,G,S)
Extracellular polymeric substance (EPS)
ECM
Glycocalyx
Slime
How are biofilms organised name some parts
Bulk fluid, cell clusters, voids, streamers and channels
Name the steps of biofilm formations
Initital attatchment
Irreversible attatchment
Maturation I
Maturation II
Dispersion
What can trigger biofilm formation
Dessication, antibiotics, high cell density
Production+detection of what singalling molecules can trigger biofilm formation
N-acyl homoserine lactones, oligopeptides, autoinducer-2.
Triggers in biofilm formation will or will not prompt changes in bacterial gene expression
Yes
What is the biofilm switch in Ps. aeruginosa (second messenger and effector)
Second messenger c-di-GMP and its receptor-effector FleQ
Do biofilms have emergent properties
Yes
What are emergent properties
Proteins or behaviours that arise in a complex system that aren’t predictable from study of the individual components.
Is growth slower or faster in biofilms
Slower
Are antibiotics more or less effective in biofilms
Less
Does AMR increase or decrease in biofilms
Increased via spon./mutation or HGT
What antibiotic insteasing the ability of MRSA cells to attatch to surfaces and form biofilms
Mupirocin
What antibiotic is effective against staph biofilms?
Rifampicin
What can reduce biofilm hypermutability
Antioxidants
What two oral biofilms are there? (to learn)
Gingivitis and periodinitis
What is periodonitis
Progressive, gingivitis leading to inflammation involving tissue that joins teeth to gums (periodontium) and or supporting bone
In biofilm infection of the wounds is debridgement or antibiotics more useful
Debridgement
Biofilm infection of wounds are mono- or polymicrobial
Polymicrobial
What species of Staphyloccocus are associated with biofilms
S. aureus or S. epidermidis
MSCRAMMs
Microbial Surface Components that Recognize Adhesive Matrix Molecules
MSCRAMMs are invovled in what?
colonisation and sepsis, mediate attachment of the Staph species to foreign body material and implants
Examples of MSCRAMMs
Fibronectin adhesions (FnBPA and FnBPB), collagen-binding protein (Cna), fibrinogen-binding proteins (ClfA and ClfB).
What bacteria cause and a major form of death in CF patients
Ps. aeruginosa
Calgary Biofilm Device is a technology for what
Reproducible assay of biofilm susceptibilities to antibiotics.
Antibiofilm MOA of redox-active compounds
Cell killers and matrix “killers”
