Bacteriology Flashcards
Define a species
A fundamental ecological genetic unit, that are reproductively isolated
What factors influence speciation in bacteria?
Fast generation times
Adaptive mutations
Horizontal gene transfer
What way can you get horizontal gene transfer?
Transformation, transduction and conjugation
What is transformation gene transfer?
Uptake of naked DNA by a bacteria
What is transduction gene transfer?
Bacterial DNA transferred by a phage
What is conjugation gene transfer?
DNA transfer between bacterial cells like plasmids
What is a prophage?
When a bacteriophage inserts DNA into the bacteria DNA
What is polyphasic taxonomy?
Done by consensus classification using phenotypic genotypes and phylogenic data.
What is a biofilm?
Structured populations of microorganisms and they live within their own extracellular polymeric substances
Biofilm characteristics?
High biodiversity
Retention of exoenzymes
Retention in nucleic acids
Increased antibiotic resistance
Biofilm life cycle?
Reversible attachment, irreversible attachment, maturation (colony formation) maturation 2 (continuous biofilm), dispersion/sloughing off, transport of biofilm particles.
What are biofilm particles called?
Flocs
What is the EPS?
Extracellular polymeric substances
What happens during reversible adhesion of biofilm?
They use long distance forces to hold them 5-20nm away from the surface. Little energy is needed to remove the biofilm
What happens during irreversible adhesion?
Binding is mediated by polymer bridges. Specific adhesion/ receptor based processes