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Sticky-end dephosphorylation - (May/18/2007 )

Please, help me.
I have two questions. Does phosphorylation step needed to be done only in the ligation with the blunt end restriction enzymes? Would it help if I phosphorylate the sticky-end RE?

Thank you.

-FruitflyD-

QUOTE (FruitflyD @ May 18 2007, 03:24 PM)
Please, help me.
I have two questions. Does phosphorylation step needed to be done only in the ligation with the blunt end restriction enzymes? Would it help if I phosphorylate the sticky-end RE?

Thank you.



We donot dephosphorylate when we do sticky end digestion provided the ends are not compatible.

For all blunt ends we dephosphorylate the vector

-scolix-

Both blunt end ligation and Sticky-end ligation with compatible ends need vector dephosphorylation.

However as scolix has mentioned, sticky end ligation with non-compatible ends do not need dephosphorylation.

Nevertheless in good hands, vector dephosphorylation does help decrease the background, especially when working with very large vectors >10kb. Unfortunately it is rather easy to over dephosphorylated and damaged the ends of the vector, making said vector unligatable. So dephosphorylation can be more hinderence then help.

-perneseblue-

if you dont dephosphorylate you vector with compatible end you will got all self ligated plasmid

-T. reesei-