Can the size of a supercoiled plasmid DNA be

shan1946 · #1 (**permalink**) 03-30-2007, 04:24 AM

determined by using standard DNA fragments electrophoresis ? in parallel?

hopefully Zen · #2 (**permalink**) 03-30-2007, 06:18 AM

Yes. It can be. Electrophoresis run in high heat remember? So all the intercellular bonds in DNa will be broken.

1 RE or 2 RE may be helpful to break down several fragment, to see the result easier.

DNA ladder will be needed as reference.

kmunson779 · #3 (**permalink**) 03-30-2007, 02:37 PM

No, you cannot determine the size of a supercoiled plasmid by standard electrophoresis.

You must first linearize the plasmid with a restriction enzyme to remove the supercoils, then you can determine size by comparing to a standard ladder.

Supercoiled plasmid runs at an unpredictably smaller molecular weight than linearized plasmid.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
supercoiled plasmid DNA	jahaley	DNA Techniques	3	01-16-2008 05:07 PM
Reuse of Plasmid with Insert from Agrobacterium cells	molbio123	DNA Techniques	2	08-05-2007 05:47 PM
How can we justify the appearance of supercoiled plasmid	Bhargav S	DNA Techniques	3	03-26-2007 03:45 AM
What is the size of the plasmid DNA pCMV-GFP?	andromedia	DNA Techniques	2	03-19-2007 03:20 PM
Plasmid DNA Isolation from Bacteria	domba	Molecular Biology Articles and Protocols	0	07-31-2006 11:04 PM

Member Login

Can the size of a supercoiled plasmid DNA be

DNA Forum

Discuss DNA, the molecule of hereditary. Topics include DNA structure, DNA replication, DNA function.