Bacteriophage lambda DNA ejection.

http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1976217&rendert...
This is a microscope recording showing single viruses releasing their genomes under the microscope. The viruses are particles of bacteriophage lambda, which infects E. coli but is here tricked into ejecting its DNA with no bacterial cells present. The DNA becomes fluorescent as it emerges from the phage particle, due to SYBR Gold present in the buffer solution. A continuous flow stretches the DNA so that it may be clearly visualized.

Category:

Pets & Animals

Tags:

• biology
• science
• virus
• bacteriophage
• DNA

[ppxmis1]

I'm trying to intercalate YOYO-1 stain into lambda phage DNA so I can do the kind of visualisation you're talking about. I follow a protocol from Su et al who have DNA 5pM and dye:base pair 1:4 ratio. I mix DNA and dye and incubate in dark at 37 deg for 90 mins following their paper but I see nothing. Seems like intercalation isn't working. Any ideas why it might not be working? What protocol do you use?

Mike

[pdg137]

Hi Mike,

You can view my complete protocol in my thesis on Caltech's thesis archive (look for Paul Grayson), but I suspect that your problem has to do with some specifics of what you are doing. What is your filter setup, and have you ever been able to observe YOYO fluorescence?

-Paul

[carldale]

Good Demonstration here. I do the same DNA stretching with Lambda with the YOYO-1 dye. Though my dye is quickly photobleached (10 seconds) so I am not able to capture a clip as long as yours.

Do you have any experience with electrophoretic stretching of Lambda?

Thanks

Carl

[pdg137]

Hi Carl,

10 seconds is about right for dye with no photobleaching treatment. To get the longer photobleaching time, you should look into Paul Selvin's anti-photobleaching formulation involving glucose oxidase and catalase. See my thesis at the Caltech thesis site (under Paul Grayson) for exact details.

-Paul

[irkiIIer]

are the white strips actually the dna molecules?! cuz thhat is a pretty good microscope.

[pdg137]

Yup, they sure are. The microscope doesn't actually have to be that amazing to capture single DNA molecules - what you need is extremely bright fluorescent dyes that you can attach to the DNA to make it visible.

[CuppaS00p]

Noooooo now the viruses are just proteins and never got to complete their primary function correctly D:

[jessiep02]

that is cool.

[Moshpitssser]

Good bye lambda! Do this with all virulent viruses as well so we don`t get sick :) But then some unwelcomed bacteria will cope :(

[mariobros4prez]

thats the future of viral therapy, our 3rd generation synthetic drugs won't cut i anymore, we have to take advantage of the phages

[miranda4538]

It is an spectacular video! I love to see it, Is is like to be in other dimension.

Congratulation to the author!