Restriction enzymes

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[Sarah-evkp]

Thanks a lot
I love this narrator. His voice is very calming

[C]

When making human insuli: Recombinant DNA technology was used.. So they basically extracted the human insulin gene from the source DNA (which is cut by the same restriction enzyme Ecor1). Then, they used the same restriction enzyme Ecor1 to cleave the DNA, these produces the "sticky ends" which will be joined together with the human insulin gene by T4 DNA ligase. After both the insulin gene and the plasmid are joined this is called the "Recombinant DNA". The recombinant DNA is then introduced into the host cells, (usually by heat shock) in this case they used E.coli as the host cells, then the cells take up the plasmid and produced two peptide chains of human insulin, which after being combined, could be purified and used to treat diabetics who at that time were allergic to the commercially available porcine insulin.. Today, Recombinant DNA technology is used to facilitate the production of large amounts of useful low molecular weight compounds and macro-molecules that occur naturally in minuscule quantities...

[Amaaly]

"Insulin can be made very cheaply"- and yet exorbitantly priced!

[hamamathepotato]

if the viral bacteria is able to reanneal itself though doesn't the restriction enzymes have to keep coming back to cleave to them after they reanneal?

[CaptainVelveeta]

great video...it'd be nice if the volume was up a bit...kinda hard to hear on my laptop...thanks :]

[nickparker]

I thought if the DNA is methylated then restriction enzymes wont touch it. But later in the video the restriction enzyme EcoR1 is used to cleave the bacterial DNA?

[rowal]

Why is the bacterial DNA being cleaved to make sticky ends, I thought only viral DNA was cleaved?

[lanadelrey]

how do you make the bacterial cell's own restriction enzymes work against it and cut its DNA when originally that was a defense mechanism against viruses and bacteriophages?

[bangnikabang]

you have an amazing way of explaining intricate concepts ! thanks

[ehsansalehabadi]

Thank you very much for the informative. If the restriction enzyme only targets external DNA (because you mentioned it has methylated points that recognize its DNA), then how can a bacterial DNA be used to get cut by the restriction enzyme?

[fatemehsarmadi]

Just a question...are plasmids methylene too?
Cleave restrictions enzyme Bakterielle DNA too?

[Dtrox]

Thank you so much!!!, incredible how anyone could explain me this clear before... You have my like and suscription!

[sabinazeynalova]

Thanks a lot for accessible and interesting explanation!

[rosamackenzie]

thank you so much - you are the ma of my biological dreams

[taracheng]

This is so amazing! We can utilize bacteria! To make a product that once only our pancreas could make. Thank you Sal and it's good to know it fascinates even you.

[riccardopusceddu]

how does methylase recognise the plasmid dna over the viral dna if the virus has already inserted its dna into the bacterial cell ?

[ES-nrhh]

WOW! Thank you for making it so easy to understand..read the article hundred times and still couldn't get it..thanks once again! :)

[shirmusic]

Thanks! One thing I didn't get, how do you cut the bacteria in minute 7:26. Doesn't it have a mathyl group attached to its DNA part?

[kelvin]

What a beautifully explained video from Khan academy

[cozmonauts]

So many questions, okay the biggest ones are… how did the plasmid DNA get cut? I thought it was protected from the restriction enzymes because of methylation… anyways, did it just happen that the insulin production gene was neatly arranged within two convenient palindromic sequences of DNA at each end for it to be cut out with EcoRI? Or were these sequences inserted there, and if so, how?