The following protocols allow for the purification of Genomic DNA. Your choice of protocol will vary based upon your target and the needs of your downstream experiment. More on that in the discussion below;
- Protocol #1 from Coleman labs and the main protocol we use at Biofoundry.
- Will give a low-yield, dirty sample that will nonetheless be usable for PCR. It is rare you would have any other reason for purifying genomic DNA specifically. If you need a pure sample, use one of protocols below…
- Tris-base, NaOH, whatever base you choose, the main intent is to keep the pH around 8-8.5, where DNA is most stable.
- TE buffer works well because the EDTA will inhibit enzyme activity, reducing the rate at which your DNA will be degraded
- I suspect this protocol works well for Yeast, but have not confirmed this… message our Facebook page if you know!
- This protocol is also regularly done in a thermal cycler with the original 5 minute 95°C denaturation step before your 25-35 cycles. For more info, check out the Colony PCR protocol.
Protocol: Genomic DNA Extraction with CTAB
- Protocol #2 from Coleman Labs
Protocol: Bead-Beater Genomic DNA Extraction
- Protocol #3 from Coleman Labs
In case none of these tickle your fancy, I’ll include this extra “best performing” protocol from an excellent paper that breaks down the comparative effectiveness of these techniques…
Protocol: Bead beater–phenol chloroform extraction method using STES buffer (BP1 Method)
- Best performing protocol from “Evaluation of the impact of six different DNA extraction methods for the representation of the microbial community associated with human chronic wound infections using a gel-based DNA profiling method” by Dilhari et al (2017)
- The buffers in this protocol are very easy to mix and use reagents you’ll need for plenty of other buffers.
- Chloroform is super nasty, read the MSDS and exercise maximum caution if using it.
This is actually just a small sampling of the available protocols for genomic DNA purification. If the boil technique isn’t working for you and you can’t afford a bead-beater, explore the web and hunt down a new protocol. If it works, let us know!