Bacteriophages

Question 1

Bacteriophages are?

Answer 1

the best-studied bacteriophages infect E.coli (gram-negative)

Question 2

what kind of genome do the bacteriophages posses?

Answer 2

linear dsDNA genomes

Question 3

do they have envelopes or not?

Answer 3

most are naked, but some posses lipid envelopes

Question 4

Two types of bacteriophages?

Answer 4

• Virulent phage

- Temperate phages

Question 5

The virulant phages ?

Answer 5

infection of host cells walways leads to replication resulsting in host cell lysis (lytic pathway T4)

Question 6

The temperate phages has two options ?

Answer 6

1) lytic pathway

2) lysogenic pathway (genome becomes incorporated into the bacterial host genome) (lamda does this)

Question 7

who discovered lamda?

Answer 7

Ester lederberg

Question 8

How is adsorption in the T4 bacteriophage?

Answer 8

T4 attaches to the core region of LPS by the tail fibers

Question 9

Following attachment?

Answer 9

the tail sheat contracts, forcing the central core through the outer membrane

Question 10

c quoi qui fait qu’il peut forcer son entrée ds le outer membrane?

Answer 10

tail lysozymes digest the peptidoglycan layer,forming a small pore

Question 11

apres que the tail soit rentrer ?

Answer 11

the phage DNA is then injected into the cytoplasm of the host cell