Question

How to separate genomic DNA and plasmid?

Answer 1

during time of conjugation it get seperate by itself as u knw tubule i formed for a horter time o it got break due to which dey got seperate

Answer 2

u dint get question. Suppose i want to sequence plasmid DNA. so i need plasmid DNA in pure form. so i will extract DNA from cell. Now it will contain genomic DNA as well as plasmid DNA.
so how should i separate them?

Answer 3

this is a pretty simple task. plasmid DNA is way smaller than bacterial DNA. so, in your first step, you crack open the bacterial membrane in a sensitive way. because it is chained to the bacterial membrane, you could just centrifugate it away with the debris and get plasmid DNA. but this will get you low output.

thus, I will give you my favourite option now to prepare plasmid DNA: it's alkalic lysis. this is the basic method of many preparation kits and uses the fact that plasmid DNA is better soluble than genomic DNA because of its smaller size.
you will suspend your bacteria in somewhat like 50mM glucose, 25mM tris and 10mM EDTA (tris is the buffer of choice, EDTA will inhibit DNA-degradation by complexing Mg2+). then, add 0.2M NaOH and 1% SDS. your DNA will fall out throguh incubation for 10min or so.
next, add 3M Kalium acetate to neutralize the NaOH and to precipitate the SDS (you may add a few drops chloroform to do that more effectively) and give the supernatant into a new tube. it should contain plasmid DNA and no genomic DNA.

Answer 4

this not going to work. no matter how u break cell , genomic DNA will be broken and u will get it along with plasmid if your using above method

Answer 5

MANUALLY U CAN SEPERATE THEM BY CENTRIFUGATION(PARTICULARLY BY ULTRA CENTRIFUGE)