Mobile genetic elements lecture 1

Question 1

Which recombinase in CSSP attacks and binds a 5’ phosphate

Answer 1

Serine recombinases

Question 2

Hin interacts with which recombination recognition sites?

Answer 2

Hix

Question 3

FljB encodes what protein

Answer 3

H2

Question 4

FljA encodes which proteins

Answer 4

H1 repressor

Question 5

Salmonella use which recombinase and sites to invert the promoter controlling FljA and FljB expression

Answer 5

Hin recombinase and Hix sites

Question 6

Name a serine recombinase

Answer 6

Hin recombinase

Question 7

Name 3 tyrosine recombinases

Answer 7

Cre, Flp and lamba int

Question 8

What part of the DNA is cut to allow for recombination

Answer 8

The asymmetrical cross over region between the recombination recognition sites

Question 9

How does strand exchange occur in serine recombinases?

Answer 9

By rotation of the flat hydrophobic interface between the dimer of dimers

Question 10

Describe the steps of tryosine recombinase mediated CSSR

Answer 10

1) 2 strands are cut, one in each of the dsDNA strands cross over regions. 2) The ends reoin and create a holliday junction. 3) 2 further strands are cleaved and rejoin to separate the 2 strands