Lec 2 - 3 - Bacterial Genetics Flashcards
a preferential outgrowth of selected clones
selective advantage
staph aureus has antibiotic resistance thanks to blank like plasmids and transposons
extrachromosomal elements
some pathogens only become virulent only after acquiring blank like a vector
mobile genetic elements
pathogen stops producing a certain protein that was recognized by antibodies
phase variation
pathogen changes the protein that it is producing to a different form
antigenic variation
RNAP is directional and goes blank
one way
three mechanisms for genetic variation
random mutation, non random (programmed), direct/indirect transmission
arise from errors made during dna replication that alter genome of a single bacterium
random mutations
example of random mutations causing resistance to blank
streptomycin
non random variation is caused by different antigenic variants of blank
Opa gene/protein
non random variation makes it really hard to develop blank
vaccines
there are blank opa genes in the chromosome
8-11
non random variation is due to blank mutations from blank making mistakes
frameshift, dna polymerase
repetition of dna sequence
duplication
flip flop of dna sequence
inversion
dna inversion controls blank in salmonella typhimurium so bacterium can swim through mucous to get to epithelium
flagellar phase variation
flagellar phase variation is due to proteins switching between these two forms
H1, H2
enzyme incoded by the invertible gene
Hin
four mechanisms for exchange of genetic information and are either direct or indirect transmission
transformation, transduction, conjugation, transposition
uptake of naked dna
transformation
transfer involves a bacteriophage
transduction
cell to cell contact transmission
conjugation
mobile genetic elements
transposition
most famous experiment for transformation
griffith
long rod like structures composed of polymeric arrays of a single pilin protein
pili
pili are involved in blank
adhesion of bacterium to cells and surfaces
blank variation occurs when there is an error in homologous recombination which is called aberrant recombination
phase variation
dna transfer via dna packaging mistakes during bacteriophage morphogenesis
transduction
transduction is used a lot in the lab to blank
create new strains
extrachromosomal elements that are stably inherited
plasmids
some plasmids have the ability to blank which means move from one bacteria to another
conjugate
during conjugation, there is an exchange of genetic material through blank
cell to cell contact
genetic elements that can go from one site in dna to another site
transposons
transposition does not require blank regions between transposon and site of transposition
homologous
transposon insertion usually requires a blank which interacts with the blank
transposase, inverted repeats
