Chapter 8

Question 0

Transcription

Answer 0

Copying of DNA into RNA

Question 1

Cell accesses it’s data in genome via…

Answer 1

Transcription

Question 2

RNA is based off _______ DNA strand

Answer 2

Complementary strand

Question 3

Define holoenzyme

Answer 3

Holo means all inclusive

Consists of core polymerase and sigma factor required for initiation

Question 4

What process needs polymerase?

Answer 4

Required for elongation

Question 5

What process requires sigma factors?

Answer 5

Initiation

Question 6

What do sigma factors and RNA polymerase do?

Answer 6

They bind and guide RNA to specific DNA sequences called promoters

Question 7

What do you call a sigma factor that is made in large quantities and used all the time?

Answer 7

Housekeeping sigma factor

Question 8

Consensus sequence

Answer 8

DNA sequence similarities among different promoters recognized by the sigma factor
Consists lf most likely base of each position of predicted promoter

Question 9

Three stages of transcription

Answer 9

Initiation, elongation, termination

Question 10

Describe initiation ( transcription)

Answer 10

Sigma factor of holoenzyme binds promoter to dna
Promoter unwinds one helical turn
RNA polymerase binds
Open complex form of RNA polymerase begins transcription

Question 11

Describe elongation ( transcription)

Answer 11

RNA chin is extended by sequential addition of ribonucleotides from nucleoside triphosphate
Sigma dissociates after 9 bases
Original RNA polymerase continues along template
Unwinding makes 17 bp bubble
Positive supercoils upstream are removed by DNA topoisomerase

Question 12

Describe termination (transcription)

Answer 12

RNA pol detached from DNA

Question 13

Rho dependent termination

Answer 13

Relies on rho protein and a strong pause site at 3’ end

Question 14

Rho independent

Answer 14

Requires GC rich region that causes RNA stem and loop to form and causes RNA pol to pause

Question 15

Rifamycin

Answer 15

Selectively binds to bacterial RNA pol and blocks RNA from leaving RNA polymerase, inhibits transcription initiation

Question 16

Actomycin

Answer 16

Intercalated between GC base pairs and mimics and DNA base
Inhibits transcription elongation
Not selective for proks

Question 17

tmRNA

Answer 17

Free ribosome stuck on damaged mRNA and has properties of tRNA and mRNA

Question 18

Catalytic RNA

Answer 18

Associate with some protein to provide catalytic activity

Question 19

Nick name for third base

Answer 19

The wobble base

Question 20

Bacteria ribosome subunits

Answer 20

60 and 40 to make 80

Question 21

Three binding sites on ribosome and describe

Answer 21

A-acceptor site, binds incoming aminoacyl tRNA
P-peptidyl tRNA site, harbors tRNA with the growin polypeptide chain
E-exit site, binds a tRNA recently stripped of proteins

Question 22

Peptidyl transferase and shine-dalgarno

Answer 22

Peptidyl transferase enzyme activity forms peptide binds between amino acids
Shine dalgarno sequence binds to rRNA and positions the start codon in the p site

Question 23

Examples of antibiotics

Answer 23

Streptomycin, tetracycline, erythromycin

Question 24

What antibiotics present translocation

Answer 24

Erythromycin, fusidic acid

Question 25

What removes N-formylmethione?

Answer 25

Methionyl aminopeptidase

Question 26

Degron

Answer 26

``` Dragon They degraded(aka destroy)'proteins ```

Question 27

Proteases

Answer 27

Destroy proteins

Question 28

Srp

Answer 28

Signal recognition particle | Helps proteins get inserted in the membrane

Question 29

SecYEG translocon

Answer 29

Moves unfolded proteins to where chaperones will take over

Question 30

Twin Argonne translocase

Answer 30

Moves folded proteins across inner membrane

Question 31

Type 1 protein secretion

Answer 31

Moves certain proteins directly from the cytoplasm to extra cellular matrix

Question 32

Which is harder to sequence, euks or proks?

Answer 32

Euks due to introns and exon

Question 33

Orthologous

Answer 33

Identical function, different organisms

Question 34

Paralogous

Answer 34

Slightly different functions in cell