Cell and Molec

[Lukas!]

The guy who typed up our lab manual did a pretty bad job. This is how he tried to explain transformation efficiency:

# colonies/mL/microgram DNA

I can't tell if he meant (# colonies)/(mL/microgram) or what...he didn't write out an example either.

Anyway. Here's the problem:

 

You need 8x 10E9 colonies. If you only have .0053 micrograms of DNA and you could only have maximum (I know it should be "a maximum", which just goes to show you how little he cares) of 1 mL of transformed cells. What efficiency would you need to get that many colonies?

 

Could somebody please show me how to set up the equations for this? I also need to figure out what efficiency means. I assume it is a way to quantify how many colonies integrated the DNA into their plasmids. However I can't get anywhere if I don't understand the units. I am going to be seeing this on an exam, so I NEED to know how to do this. I got 4.24 E7 micrograms per milliliter.

 

Also, I used dimensional analysis to solve this problem:

If you get 400 colonies per plate. How many plates would you need? I got about 20 million. This seems excessive to me. Could somebody let me know if that is correct?

 

Finally it asks me what volume of transformed cells would you be putting on each plate...I got 5 times 10 to the negative 8 mL.

 

I think all of my answers are wrong. I went to the professor who wrote the lab manual for help and he sent me away. He's been a real jerk. HELP!!!