Transport/storage of samples prior to DNA Extraction

[msmdejesus]

Hi.
I will be collecting nasal swabs and stool swabs from pet dogs. What is the best medium or buffer to hold the samples prior to bacterial DNA extraction. I know I can hold the samples at room temperature. I am thinking of TE buffer or phosphate buffer. This is for metagenomics study.

Thank you in advance for your prompt feedback and generosity.

Sheila
Philippines

[smhall]

I would probably use and SDS+EDTA solution (unbuffered). You are only interested in the DNA, which you can clean up with standard phenol/CHCl3/isoamyl alcohol. The rationale is the EDTA to inhbit metal-dependent enyzmes or processes, and the SDS will basically denature any destructive proteins (enzymes) which might degrade your DNA, and the SDS will be sufficiently bacteriostatic at a 1 or 2% level. I suppose I would use 10-50 mM EDTA.

Moreover, I would heat it up to 60-70 degrees C as well for 15-20 min, which will help the SDS denature the biomolecules.

For the extraction, consider adding sodium hydroxide, at a concentration used for alkaline lysis of bacteria for extracting DNA.

[Indres]

Thanks for answer, had a quite similar question recently.