T4 DNA ligase still usable after a night out? - (Jan/24/2008 )

hi....i would just like to know if a T4 DNA ligase which has been left outside overnight (20-23°C) is still usable? what is its half-life?

The ligase is probably fine, but the buffer, which has ATP in it, may not be. You can probably add some ATP to the buffer and continue to use it. The real answer, if you care, is to assay it.

Yea, the ligase will be fine. Overnight isnt that bad. Unless you really heat it up.

You could do a positive control ligation and try it out. or get another one.