MIC428R Final

Question 1

If two different restriction enzymes target the same sequence, the overhands will be able to bind to each other

Answer 1

False

Question 2

Which of the following istes on the bacterial chromosome can recombine with attP?
xis
attP
int
attB

Answer 2

attB

Question 3

Spacer arrays found in CRISPR loci are transcribed and then processed into small crRNA that target incoming DNA or RNA

Answer 3

True

Question 4

H-NS protein binds ti regions that are relatively high in GC%

Answer 4

False

Question 5

Which of the ofllowing proteins is an antiterminator?
M
P
N
O

Answer 5

N

Question 6

Phage lambda chooses the lysogenic cycle when CI repressor is not degraded by proteases

Answer 6

False

Question 7

Which of the following proteins is a site specific recombinase?
RecA
Int
TnpA
RecF

Answer 7

Int

Question 8

Phage lambda chooses the lytic cycle a majority of the time under normal conditions

Answer 8

true

Question 9

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

Answer 9

PAM

Question 10

The restriction enzyme EcoR1 leaves what type of overhang?
4 base 3’
4 base 5’
a blund end

Answer 10

4 base 5’

Question 11

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

Answer 11

Modificaton of CI so that it cannot autocleave
Modification of recA so that it cannot be activated

Question 12

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’

Answer 12

ssDNA with a sequence 5’ AAAAAAAAAAAAAAAA 3’

Question 13

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

Answer 13

M9 minimal media + glucose
LB
M9 minimal media + maltose

Question 14

The restriction enzyme EcoRV leaves what type of overhand?
blunt end
4 base 3’
4 base 5’

Answer 14

blunt end

Question 15

The restriction enzyme Psti leaves what type of overhang?
4 base 5’
4 base 3’
blunt end

Answer 15

4 base 3’

Question 16

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

Answer 16

no colonies on m9 mm + lactose

Question 17

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

Answer 17

no colonies on m9 mm + lac

Question 18

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

Answer 18

white colonies on m0 mm + glucose + Xgal

Question 19

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

Answer 19

Blue colonies on m9 mm + glucose + Xgal

Question 20

Mutation rates would likely decrease after UV exposure with deletion of which of the following genes?
recA
DNA photolyase
mutS
uvrA

Answer 20

recA

Question 21

Which of the following likelty interacts with RecA in any state?
SetR
DinI
C1
UmuC

Answer 21

All of them

Question 22

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

Answer 22

Dimer separation by DNA photolyase

Question 23

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

Answer 23

Decreased mutation rate when exposed to UV
Decreased homologous recombination rates
Increased sensitivity to UV
Deceased induction of lambda phage

Question 24

RecFOR changes its function when it encouters chi sites

Answer 24

False

Question 25

Hihly expressed genes will experience lower overall mutation rates than lowly expressed genes

Answer 25

True

Question 26

Deletion of DAM methylasewill lead to increased mutation rates within E. coli

Answer 26

true

Question 27

Deletion of DNA Pol IV will lead to increased mutation rates within E. coli cells

Answer 27

False

Question 28

ICE elements (like SXT) experience high levels of conjugation in cells where SetR has been genetically modified so that it cannot be cleaved

Answer 28

False

Question 29

Transcription coupled repair recruits UvrAB to help carry out nucleotide excision repair in damaged regions of DNA

Answer 29

True

Question 30

E coli will be less sensitive to damage by UV radiation if they are grown in light

Answer 30

True

Question 31

RecA changes its function when it encounters chi sites

Answer 31

False

Question 32

RecBCD changes its function when it encounters chi sites

Answer 32

True

Question 33

E coli cells will be more sensitive to damage by ROS if they are grown in light

Answer 33

False

Question 34

Vibrio cells produce small peptides (translated from ORFs) that act as quorum sensing signals

Answer 34

False

Question 35

Under high osmolarity conditions, EnvZ will act as a Phosphatase Kinase

Answer 35

Kinase

Question 36

OmpR can carry out the following functions Phosphorylation of OmpR Binding to OmpC promoter Binding to OmpF promoter De-phosphorylation of OmpR

Answer 36

Bind to OmpC and OmpF promoters

Question 37

Gram positive cells produce small peptides that act as quorum sensing signals

Answer 37

True

Question 38

Bacterial cells from different species can communicate with one another through quorum sensing

Answer 38

True

Question 39

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

Answer 39

LuxR+ and Luxl+ strains

Question 40

EnvZ can carry out the following functions Phosphorylation of OmpR Binding to OmpC promoter De-phosphorylation of OmpR Binding to OmpF promoter

Answer 40

Phosphorylation of OmpR De-phosphorylation of OmpR

Question 41

Each bacterial species makes only one types of quorum sensing signal

Answer 41

false

Question 42

Phosphorylated NtrB binds more strongly to DNA than unphosphorylated NtrB

Answer 42

false

Question 43

OmpF provides a relatively large channel in the inner membrane

Answer 43

false

Question 44

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

Answer 44

Deletion of the polyU region downstream the leader peptide in the attenuator region

Question 45

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

Answer 45

trpE expression

Question 46

Which of the following is constitutively expressed RpoS RpoH RpoD RpoN

Answer 46

RpoH RpoD RpoN

Question 47

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

Answer 47

A nonsense mutation in the second codon of the leader peptide

Question 48

Which of the following is directly involved in positive regulation of the lac operon? Lac operator LacZ LacI CAP binding site

Answer 48

CAP binding site