Biotech 2nd Edition Sample Ch. 4 Biotechnology Sample Ch. 4 - Page 17

Laboratory 4g Bacteria Cell Culture Background For DNA extraction purposes, it is desirable to use a broth culture of cells. The broth culture must be “started” 1 or 2 days in advance, from a plate culture, to ensure that there is a high density of cells in the culture. The broth culture is started from a single colony grown on agar plates. Using a single colony of identical cells ensures that all cells in the broth culture are identical (see Figure 4.9). Materials Laminar flow hood or biosafety cabinet hood Lysol® disinfectant LB agar plates/broth (from Labs 4e and 4f) E. coli, stock plate Glasses, safety, plastic Bunsen burner Lab gas lighter Inoculating loop, Ni/Cr wire or sterile, plastic, disposable inoculating loops Incubator oven, 37°C Tubes, 50 mL, sterile, conical Tube racks for 50-mL tubes Pipets, 10 mL Pipet pump, green Water bath, 37°C, shaking Figure 4.9.  Bacterial cell cultures are started on agar Petri plates. Using a sterile inoculating loop on a sterile bench, a sample is streaked out until some cells are spaced individually on the agar. H