Genomic DNA extraction from filters - (Jun/04/2013 )

Dear all

I am wondering if anyone has experience in extracting prokaryotic genomic DNA (gDNA) from filters using a commercially available kit.

We have started trying to extract gDNA from air samples collected onto filters, using the PowerSoil kit from Mo Bio Laboratories, but have not had much luck; there was no sign of DNA as suggested on the NanoDrop.

Has any of you used modifications of this kit, or have used other kits to acquire gDNA? I have a feeling it is the low amount of microorganisms collected on the filters, but I am new to this project, and would like to just hear about different opinions regarding this issue.

Thank you very much.

It is very unlikely that you could see DNA extracted from air filters on a nanodrop. Typically, this DNA would be used in a PCR reaction with universal bacterial 16S primers, which were then purified, and either cloned for conventional sequencing, or end-tagged and used in high throughput sequencing.

Thanks. We are going to use universal 16S primers for sequencing. So you are saying NanoDrop does not give an indication of whether there is DNA or not from these samples? I mean if there is no NanoDrop reading, chances are that there will be unsuccessful DNA amplification...?

Thanks

PCR can easily amplify DNA which is completely invisible on a gel or unmeasurable in a nanodrop. In principle, a single molecule can be amplified.