I'm am struggling with genomic DNA extraction from different samples of Pyura chilensis; the DNA is degraded as can be seen on the gel.
We've always used GeneJET Genomic DNA purification Kit (by ThermoFisher), and it works fine for samples from other species; so the kit isn't the problem.
We've always used tissue samples stored in 95% Ethanol (which are washed with water prior to DNA extraction), but the problem persists irrespective of whether the samples are one day old or a few years old. The storage method seems to work fine for gDNA extraction from other species.
Then, my guess is that the problem is with Pyura itself. So I have to figure out if either the extraction or the storage isn't appropriate for Pyura. I read that Pyura has a lot of copper in it. We planned to use a new buffer for storing it: salt Saturated DMSO, containing EDTA.
I would like to ask if any of you have ever worked with this organism (and if you have, then how did you manage to extract DNA from it). Do you have any suggestions on any DNA purification protocols?