We use (adding even) lysostaphin to lysis of gram positive staphylococci. Animal tissue may require homogenization?

of course you have to homogenize tissues as Szymon sayed, and i think that's will work but if you didn't get a good results you can use High pure RNA isolation kit from Roche, it work very well with lysozyme, also you can use heat shock for the lysis using water bath or thermal cycler.

We homogenize tissues and use lysozyme and lysostaphin pretreatment with lysis buffer following commercial kit for DNA isolation. But after tissues homogenization your protocol should work for them too.

We've had good success including a bead-beating step with 0.1mm beads. This seems to overcome chemical limitations for some difficult to lyse gram positives.

You might also need to extend the Proteinase K digestion step, up to 3 hours, with regular vortexing during this incubation time. (Or use a thermo shaker.) 

It is easy to see when the tissue is digested. And really tough tissue can also be left for overnight incubation.

Try to homogenize tissues in the presemce of protease inhibitor such as lysozyme and lysostaphin followed by proteinse K treatment and then follow any Qiagen DNA purification kit.

Regards,

GCK

For extraction of Gram positive DNA from animal tissues one can use glass beads, lysozymes or lysostaphin folllowed by a lengthy proyeinase K dighestion. See if that works.

GCK

Thank you, can u share with me the protocol? How do I use glass bead, is that for homogenizing?

others have already mentioned mechanical lysis methods after enzymatic incubation, RBB or  bead beating. not sure if your kits protocol includes this type of lysis. Also mutanolysin in combination with lysozyme with a 15 minute incubation at 55 degrees celsius works well for me, followed by proteinase k digestion at the same temperature for 15 minutes. these additonal steps should be carried out prior to adding the kits lysis buffer. what type of work are you doing with the DNA? does it have to be high molecular weight?

Actually I have tried extracting mycobacteria DNA from culture broth using protocol for gram negative bacteria, only proteinase K digestion at 55C for around 1hr, the PCR work very well, and someone share with me, they can do their PCR by dipping the bacterial culture directly into the master mix, and  95C at the begining of the PCR is enough for releasing DNA content, seem that we can have more faster extraction protocol?