Protocol for preparation of DNA for pulsed-field gel electrophoresis: isolation of intact DNA from yeast. Yeast cells are first treated enzymatically to break down the cell walls and then resuspended in low-melting-temperature agarose plugs. The DNA is liberated by infusing the plugs with lysis buffer and proteases. This method is used to prepare both conventional and artificial yeast chromosomes. - [Read Preparation of DNA for Pulsed-field Gel Electrophoresis: Isolation of Intact DNA from Yeast]