Question

can someone explain why the mechanism for tyrosine recombinate attacks with the 5'-OH when other types all attack with 3'-OH?

Answer 1

do you have the proposed reaction mechanisms for these?

Answer 2

yes mechanism for tyrosine slide 9.

Answer 3

other mechanisms in general use the 3'-OH

Answer 4

do you think you could post it as a pdf, i don't like saving things to on word, or powerpoint.

Answer 5

um ill try idk how to change files to pdf

Answer 6

nvm i did it

Answer 7

well it looks like the enzymes cleave at different places, so i guess you can't attack with the OH that's being occupied by the phosphate.

Answer 8

ok so i guess it depends where the recombinates are on the strand. so that means that most examples use a serine like mechanism and the tyrosine mechanism is rare?

Answer 9

i think it depends where the cleavage occurs, the Tyr one leaves the 5' OH free to act as a nucleophile, while the Ser one leaves the 3' OH free.

It probably has to do with steric hindrance because the R group of Tyr looks like

Answer 10

and serine is much less hindered.