I need a DNA protocol extraction because a work with Arthrobacter genus bacteria and all the protocols I try result in a low concentration of DNA and high concentration of ARN.
Lysostaphin treatment followed by treatment with proteinase K / NaCl and separation of organic and aqueous phase with chloroform-Isoamylalcohol was adequate for me. Please check Chloroform-Isoamylalcohol method for DNA extraction in Gram positive bacteria
I would suggest you try using an enzyme called lysostaphin. It is meant to be specific for aiding the lysis of the cell wall of Staphylococci, but I found it useful for other Gram positive bacteria.