Beginning E. coli growth

It’s been a while since I’ve had to grow e. coli and I’ve never really had to measure E. coli growth, just because I would vaporize the cells immediately to get at their precious nectar (plasmid DNA), but now I have to do all that. So I’m learning on the fly, the best way to learn.

Yesterday Alex and I started two colonies from E. coli that is designed to grow pBluescript and anther designed to hold pALS (my custom plasmid). Here are her notes on the matter (scroll down to read some comments from myself).

This morning we got acquainted with the cuvette reader on the Nanodrop and here are Alex’s notes on that. In summary we got an OD of 0.714 on the one test tube that grew bacteria. Now I have to figure out what that number means and how to accurately measure OD in the future. For that I’ll need to find some protocols that explain all about measuring cell cultures and do something with making a standard curve, which is talked about here.

In preparation I’m doing another starter culture that I’ll check on in 36 hours (or so) and begin dilutions and what not. My starter culture is literally just LB broth resuspended in DI water purchased from Sigma, without antibiotics (since I don’t really care what grows as long as something does, for now and because we don’t have any). I put a scrape of the Stratagene competent cells into the broth and put it in our shaker at 37C, 150 RPM, left for overnight and beyond.