blunt-end ligation problem - (May/31/2006 )
hi friends
 I have problem with blunt-end ligation my vector (5900bp) and my insert around(1200bp)
i do blunt-end ligation with PEG 8000 and with out PEG 8000 i always get the vector when i run it on gel 
 if some one know how to do it the right way for blunt-end ligation  please help me   
 my condition 
     the ratio (1:5) vector:insert
      1 μl of 10X Ligase Buffer
   0.3 μl of 10 mM ATP
   2 μl of 40% PEG 8000 )
   0.3 μl of 6.66 Weiss Units/μl T4 DNA Ligase (New England Biolabs) 
5. Add the cocktail prepared in Step on ice. 
6. Incubate at 16°C for 1 hour. 
   thank you
Hi,
did u dephosphorylate the vector before ligation?
i think you need more time for do the ligation... blunt-end ligation need almost 24 hours at 16°C. 
Did you make alicuots of buffer?...  see the recommendations of NEB.
regards
I agree with donisaid.
In my humble opinion,u can not complete the blunt end liagation in just 1h with such a low concentration of T4 ligase.
Dephosperazation is also needed.
