M2 L2

Question 1

3 steps of transcription

Answer 1

Initiation
Elongation
Termination

Question 2

Promoters are…

Answer 2

Upstream dna sequences where dna pol bind

Question 3

Sigma factor

Answer 3

Protein subunit of RNA pol responsible fpr dna binding

Question 4

Where does sigma factor bind to

Answer 4

Major groove

Question 5

Beta helices of sigma factor bind to dna major groove
T/F

Answer 5

FALSE
Alpha factors bind

Question 6

Sigma factor tells rna pol where promoter is and then sigma factor binds to major groove

Question 7

Which specific groove do sigma factors bind to upstream transcriptional regulation

Answer 7

-35/-10

Question 8

What does initiation site usually contain

Answer 8

Tatatat purines flanked by prymidines

Question 9

Function of sigma 70

Answer 9

Exp of housekeeping genes

Question 10

Sigma 32 has what reponse

Answer 10

Heat shock response

Question 11

Function of s sigma

Answer 11

Stress signal

Question 12

Alternative sigma factors regulate genes

Answer 12

Yesss

Question 13

What imp does diff sigma factor recognising diff consensus sequence has

Answer 13

Genes are only expressed when needed
But all bind to -35 and -10

Question 14

Subunits of rna pol

Answer 14

Alpha aplha beta beta prime
RpoAA
RpoBC
Hloenzyme
Sigma factors
Rpoz

Question 15

What is holoenzyme

Answer 15

Subunit of rna pol
Alpha alpha beta beta prime + sigma factor= core enzyme+ sigma factor

Question 16

RpoA

Answer 16

Subunit of rna pol
Two subunits from same gene

Question 17

RpoB/C

Answer 17

Subunit of rna pol
Two diff catalytic subunit/ diff genes

Question 18

RpoZ

Answer 18

Stability of beta prime into core enzyme

Question 19

What is the bi subunit of rna pol

Answer 19

Beta prime

Question 20

What is closed complex

Answer 20

Sigma factor recognises promoter
Dna is ds DNA

Question 21

RNAP floats around and bins to dna unspecific untill sigma factor makes it recognise

Question 22

What is open complex

Answer 22

DsDNA is pulled apart

Question 23

What happens during initiation of transcription in prokaryotes

Answer 23

Rna pol binds non sprcifically
Sigma factoprs help rna pol to bind at promoter
Closed complex forms
Open complex forms
Transcription iniates at purine

Question 24

What happens duringt elongation

Answer 24

Additon of sucesssive nucleotid3es
Sigma factor is releases

Question 25

Function of triphosphate

Answer 25

During elongation it is added to 3’ OH of growing chain

Question 26

Rifampicin mechanism

Answer 26

Stops elongation Affects beta subunits of RNAP

Question 27

How does rifampicin resistance works

Answer 27

Mutation occurs in bacterial rpoB gene changes amino acid sequence = protein structure changes change in st of beta subunit binding site of ramficinb is altered

Question 28

what is the result on bacterial cell because of ramficin resisntance

Answer 28

It cant bind Rna pol works elongates Bacteria survive

Question 29

How can rifampicin resistance be detected in bacteria? ## Footnote Detection methods help identify resistant strains and inform treatment options. Hint: Genetic analysis of rpoB mutations and binding tests.

Answer 29

Detection methods include genetic testing for mutations in the rpoB gene and assessing the binding affinity of rifampicin to RNA polymerase. ## Footnote These methods help identify resistant strains and inform treatment options.

Question 30

detection of rampifin resistancxeee

Question 31

How does rifampicin inhibit transcription in bacteria

Answer 31

Binds bw rpob and rpoc subunits of rna pol

Question 32

How rna pol work with rifampicin

Answer 32

Will start transcription cant elongate — displaces rna nucleotides- stops elongation

Question 33

How does rifampicin resistance happen

Answer 33

Sub of serine , aspartate or histadine — doent let rifampicin to bind— no HB forming

Question 34

How to identify rifampicin resistance

Answer 34

genXpert- qPCR — fluroscent outcome- SYBR nd taqman— probes

Question 35

for genXpert how many probes do we use

Answer 35

probe A B C D E

Question 36

Which probe in genXperrt binds at mutation

Answer 36

probe A nd E - bind at rpoB- mutaion vs non mutation

Question 37

How are fluroscents used to identify rifampicin rifampicin resistance using genXpert

Answer 37

taqman and SYBR