T4

Question 1

Three struct?

Answer 1

1. Head
   - icosahedral; linear dsDNA
2. Tail sheath
3. Base plate
   - Long tail fibres and baseplate pins

Question 2

Describe attachment

Answer 2

Long tail fibre binds complementary to specific receptor sites

Question 3

Describe penetration

Answer 3

• releases phage lysozyme;
• digest bacterial peptidoglycan cell wall;

AND

-baseplate pins attach irreversibly;

• > tail sheath contracts;
• > inject dsDNA, help from pilot protein

Question 4

Describe synthesis

Answer 4

• bacteriophage genome replicates;

- components pxed; host machinery

Question 5

How is viral DNA replication done?

Answer 5

Transcribed to viral mRNA by host ribosomes, tRNA, translation factor

Question 6

Describe assembly

Answer 6

• n.a and protein subunits assembled into new virus

- assembled independently

Question 7

Describe release

Answer 7

• phage codes lysozyme breaks down peotidoglycan

- > osmotic lysis