MIC428R Final Flashcards
If two different restriction enzymes target the same sequence, the overhands will be able to bind to each other
False
Which of the following istes on the bacterial chromosome can recombine with attP?
xis
attP
int
attB
attB
Spacer arrays found in CRISPR loci are transcribed and then processed into small crRNA that target incoming DNA or RNA
True
H-NS protein binds ti regions that are relatively high in GC%
False
Which of the ofllowing proteins is an antiterminator?
M
P
N
O
N
Phage lambda chooses the lysogenic cycle when CI repressor is not degraded by proteases
False
Which of the following proteins is a site specific recombinase?
RecA
Int
TnpA
RecF
Int
Phage lambda chooses the lytic cycle a majority of the time under normal conditions
true
The Presence of what kind of motif specifies whether CRISPR complexes target incoming DNA?
Proto Spacer Adjacent (PAM) motif
CASCADE motif
Csy4 motif
Phage motif
PAM
The restriction enzyme EcoR1 leaves what type of overhang?
4 base 3’
4 base 5’
a blund end
4 base 5’
Once phage lambda is a lysogen, which of the following modifications will cause the phage to be permanently stuck as a lysogen?
Deletion of LexA
Modification of CI so that it cannot autocleave
deletion of CI
Modification of recA so that it cannot be activated
Modificaton of CI so that it cannot autocleave
Modification of recA so that it cannot be activated
Which of the following could be recognized by a CRISPR spacer with the TEMPLATE sequence (note this doesn’t say crRNA, note the type of DNA/RNA targeted, and all the answers are the same length as the spacer, so don’t worry about length being different and assume the CRISPR can target ssDNA).
3’ AAAAAAAAAAAAAAAA 5’
ssDNA with a sequence 5’ AAAAAAAAAAAAAAAA 3’
ssDNA with a sequence 5’ GGGGGGGGGGGGGGGG 3’
ssDNA with a sequence 5’ AAAAAAAAAAAAAAAT 3’
ssDNA with a sequence 5’ TTTTTTTTTTTTTTTT 3’
ssDNA with a sequence 5’ AAAAAAAAAAAAAAAA 3’
You select for a strain of E. coli that is RESISTANT to lysis/lysogeny from phage lambda. The mutation providing resistance eliminates the lambda receptor. The resistant strain will be able to grow well on which types of media?
M9 minimal media
M9 minimal media + glucose
LB
M9 minimal media + maltose
M9 minimal media + glucose
LB
M9 minimal media + maltose
The restriction enzyme EcoRV leaves what type of overhand?
blunt end
4 base 3’
4 base 5’
blunt end
The restriction enzyme Psti leaves what type of overhang?
4 base 5’
4 base 3’
blunt end
4 base 3’
The order of the lac operon is lacZYA
If a Tn5 transposon lands in lacY, the phenotypic outcome would be:
White colonies on M9 mm+ lactose
Blue colonies on M9 mm + lactose
No colonies on M9 mm + lactose
no colonies on m9 mm + lactose
The order of the lac operon is lacZYA
If a Tn5 transposon lands in lacZ, the phenotypic outcome would be:
White colonies on M9 mm + lactose
Blue colonies on M9 mm + lactose
No colonies on M9 mm + lactose
no colonies on m9 mm + lac
The order of the lac operon is lacZYA
If a Tn5 transposon lands in lacZ, the phenotypic outcome would be:
White colonies on M9 mm + glucose + Xgal
Blue colonies on M9 mm + glucose + Xgal
No colonies on M9 mm + glucose + Xgal
white colonies on m0 mm + glucose + Xgal
The order of the lac operon is lacZYA
If a Tn5 transposon lands in lacY, the phenotypic outcome would be:
White colonies on M9 mm + glucose + Xgal
Blue colonies on M9 mm + glucose + Xgal
No colonies on M9 mm + glucose + Xgal
Blue colonies on m9 mm + glucose + Xgal
Mutation rates would likely decrease after UV exposure with deletion of which of the following genes?
recA
DNA photolyase
mutS
uvrA
recA
Which of the following likelty interacts with RecA in any state?
SetR
DinI
C1
UmuC
All of them
Which of the following DNA repair pathways does not require ligase?
Base excision repair
Nucleotide excision repair
Dimer separation by DNA photolyase
Methyl directed mismatch repair
Dimer separation by DNA photolyase
Which of the following are phenotypes associated with deletion of recA?
Decreased mutation rate when exposed to UV radiation
Decreased site specific recombination of ICE elements
Decreased homologous recombination rates
Increased sensitivity to UV radiation
Increased induction of Lambda prophage
Decreased induction of Lambda prophage
Decreased mutation rate when exposed to UV
Decreased homologous recombination rates
Increased sensitivity to UV
Deceased induction of lambda phage
RecFOR changes its function when it encouters chi sites
False
Hihly expressed genes will experience lower overall mutation rates than lowly expressed genes
True
Deletion of DAM methylasewill lead to increased mutation rates within E. coli
true
Deletion of DNA Pol IV will lead to increased mutation rates within E. coli cells
False
ICE elements (like SXT) experience high levels of conjugation in cells where SetR has been genetically modified so that it cannot be cleaved
False
Transcription coupled repair recruits UvrAB to help carry out nucleotide excision repair in damaged regions of DNA
True
E coli will be less sensitive to damage by UV radiation if they are grown in light
True
RecA changes its function when it encounters chi sites
False
RecBCD changes its function when it encounters chi sites
True
E coli cells will be more sensitive to damage by ROS if they are grown in light
False
Vibrio cells produce small peptides (translated from ORFs) that act as quorum sensing signals
False
Under high osmolarity conditions, EnvZ will act as a
Phosphatase
Kinase
Kinase
OmpR can carry out the following functions
Phosphorylation of OmpR
Binding to OmpC promoter
Binding to OmpF promoter
De-phosphorylation of OmpR
Bind to OmpC and OmpF promoters
Gram positive cells produce small peptides that act as quorum sensing signals
True
Bacterial cells from different species can communicate with one another through quorum sensing
True
Which of the following will complement a Luxl mutant in Vibrio?
Cell free supernatant form a:
LuxR- strain
LuxR+ strain
Luxl- strain
Luxl+ strain
None of the above
LuxR+ and Luxl+ strains
EnvZ can carry out the following functions
Phosphorylation of OmpR
Binding to OmpC promoter
De-phosphorylation of OmpR
Binding to OmpF promoter
Phosphorylation of OmpR
De-phosphorylation of OmpR
Each bacterial species makes only one types of quorum sensing signal
false
Phosphorylated NtrB binds more strongly to DNA than unphosphorylated NtrB
false
OmpF provides a relatively large channel in the inner membrane
false
Which of the following will likely increase expression of trpB in E. coli
Deletion of the polyU region downstream the leader peptide in the attenuator region
Deletion of TrpA
Nonsense mutation in TrpA
Deletion of anti-TRAP
Deletion of the polyU region downstream the leader peptide in the attenuator region
Which of the following is directly regulated by changes in the ratio of uncharged/charged tryptophan tRNA
trpE expression
Attenuator region leader peptide expression
TRAP binding to RNA
TrpR binding to DNA
trpE expression
Which of the following is constitutively expressed
RpoS
RpoH
RpoD
RpoN
RpoH
RpoD
RpoN
Which of the following will likely decrease expression of the trpB in E. coli
A nonsense mutation in the second codon of the leader peptide
Deletion of the attenuator region
Deletion of TRAP
A nonsense mutation in trpE
A nonsense mutation in the second codon of the leader peptide
Which of the following is directly involved in positive regulation of the lac operon?
Lac operator
LacZ
LacI
CAP binding site
CAP binding site
