Evil SOB

One thing that happens constantly in labs that do molecular cloning is transforming bacteria, that is, making bacteria take up foreign DNA.  The way to do this is to first mix some DNA into a small amount of (transformation) competent bacteria (usually E. coli–a non-infectious lab strain; transformation competent bacteria have been treated with some chemicals beforehand) and let them sit on ice for 20-30 minutes.  Then, you “heat shock” for a little less than a minute by putting them at 42 degrees Celsius (107.6 degrees Fahrenheit) then back on ice.  This essentially freaks out the bacteria and they start taking random stuff inside the cells, including (hopefully) your DNA.  Then, you want to incubate them in a really nice, rich medium for 30 minutes to an hour to let them recover from their ordeal.

Enter the SOB.

The media that we use is called SOC.  Now, we have someone in the lab who makes our media and pours plates for us.  But, she can only do very simple things (take this packet, dissolve it in water, autoclave it) and SOC involves mixing several things and adjusting the pH.  Which means we are on our own for the SOC.  On top of that, SOC contains a large amount of glucose (sugar) which will break down if you autoclave it, so, you have to make it without the glucose, autoclave it, then wait for it to cool, then add glucose.  Before you add the glucose, the solution is known as SOB.  Which always gives me a little giggle.  I’m childish that way.

Wow, that was a long explanation for such a short punchline.

Anyway, I decided the undergrad needed to learn how to make SOC because, well, he’s an undergrad and he needs theis kinds of drudgery learning experience.  Unfortunately, once we put the stuff in the autoclave, he had to leave, so I’m left to finish it off myself.  This is really not how I thought this would end. *sigh*

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