During the blue-white screening, I am getting both blue and white colonies for ligated vector, Some colonies are light blue/ white for this when I shifted this plate from 37c to 4c so after some hours these colonies turned into dark blue at 4c temperature. I would like to inquire how 4c helps in dark blue coloration and how many hours are required for this dark colour ?
John P Hegarty
It takes 16-20 hours for β-galactosidase to be expressed and process x-gal into blue pigment. Placing your plates at 4C for 4-8 hours after the initial overnight incubation will increase pigment precipitation, enhancing the blue color of negative colonies. Also, substituting S-Gal (from Sigma) for X-gal will give you a clearer and reliable color.
2 votes
2 thanks
- Badges
- Science topic
- Similar topics
- Biological Science
- Molecular Cell Biology
More Monika Jain's questions See All
Similar questions and discussions