perneseblue

I used Promega before, now using MEGA-spin™ Agarose Gel Extraction Kit (iNtRON Biotechnology) but it did failed me once due to malfunctioned column...
Agree with phage434, There is no such thing as Best Gel Extraction Kits...

phage434, on 15 June 2011 - 01:53 PM, said:

How much is the price of your robot?

BL21 would be a very bad choice of strain to attempt cloning with. Your choices boil down to finding and using a more stable cloning strain, or finding out more about what exactly is happening. Do you have sequence for the construct you want? Do you have sequence for the plasmid that you created? That would be my first order of business. Then, I would look at what repeats and homologies exist that might explain the recombination you are apparently seeing. You'll know a lot more after doing this, if only to know that you have a severe problem. More likely, you will discover the problem is something entirely else that we haven't thought of. You should be collecting all of the information you can, using whatever tools are available, to figure out what is happening. Have you done restriction digests of the plasmids you create? These are simple and inexpensive. You can't figure out what is wrong by asking others or by waiting.

Why God Didn't Get Tenure

1. He had only one major publication.
2. It was in Hebrew.
3. It had no references.
4. It wasn't even published in a refereed journal.
5. Some even doubt he wrote it himself.
6. It may be true that he created the world, but what has he done since then?
7. His cooperative efforts have been quite limited.
8. The scientific community has had a hard time replicating his results.
9. He never applied to the Ethics Board for permission to use human subjects.
10. When one experiment went awry he tried to cover it up by drowning the subjects.
11. When subjects didn't behave as predicted, he deleted them from the sample.
12. He rarely came to class, just told students to read the Book.
13. Some say he had his son teach the class.
14. He expelled his first two students for learning.
15. Although there were only ten requirements, most students failed his tests.
16. His office hours were infrequent and usually held on a mountaintop.

Hello,
What is the best method for extracting DNA from ticks ?
I heard of a heating method of ticks in a solution of ammonium.
Thanks in advance
Lilia

I think the agarose is not polymerizing properly in this case. Give it some more time for polymerization.

I don't think the problem is the agarose. I've had this problem myself. In my experience this happened because voltage was too high or because the salt content of the samples was too high. I am guessing that your loading buffer is too concentrated. Try a different loading buffer.
Just my two cents.
Best of luck.
Miha