Dave Gray's Session 5 Email Q&A
For this email, my question was:
Lisa,
A question occurred to me today regarding our class. I hope you can answer it.
You mentioned the restriction enzymes caused problems for Craig Venter's effort for two years. I wonder why it didn't cause a problem for us. I would think the bacteria would break down our vector with restriction enzymes the same as happened for that effort. Can you explain why that didn't happen?
Thanks! (And thanks again for leading the class.)
- Dave Gray
Lisa's response was:
Hi Dave,
We didn't have any problems with restriction enzymes because we used a lab strain of E. coli in which the cell's restriction enzymes were disabled by mutation. That's why most plasmid manipulations are done in one or two engineered strains of E. coli. Venter's group used a bacterium that did not contain mutations of the restriction enzymes so they had to add methyl groups to their DNA to prevent its being cut.
Thanks for attending the first go-around of the class. I wish we had more success with the lab results but I hope it was at least useful for practicing the techniques.
Best regards, Lisa
