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2. Add diluted plasmid DNA stock (1-10 ng, e.g. dilute 1 uL of 1 ug/uL plasmid stock into 1 mL of water, and add 1 uL to bacteria) or 10 5 uL ligation reaction MAX to 50 100 uL bacteria (~5 uL is fine to be safe). Be sure that the volume of DNA solution added to the bacteria doesn’t exceed 20% 5% of the bacterial volume (20 5 uL for 100 uL bacteria, 10 for 50200 uL, etc). You can add more DNA volume (above the 5%) but note that this may decrease the efficiency of your reaction.
3. Incubate bacteria on ice for 30 minutes, then heat shock by placing in 42C water bath for 30 seconds.
4. Place tube on ice for 2 minutes then and add 0.3 mL 9x volumes of SOC (prewarmed at 37C). For example, to 100 uL of bacteria you can add 900 uL of SOC.
5. Shake for 30 60 minutes at 37C (to allow the bacteria to begin expressing antibiotic resistance, not for Amp; you technically don't need to do this for AmpR but you can if you want), and plate on an LB/antibiotic plate. Plates can be placed at 37C prior to the transformation to allow them to dry slightly.