During isolation of DNA from donor organism, DNA is precipitated by using 

For precipitating the genomic DNA separated from cell, chilled ethanol is used which helps in reducing the polar nature of water and forming ionic bonds between DNA and positive charges of the solution. Lysozyme is used to degrade the bacterial cell walls. Detergents are used to break the biological membranes and Ethidium bromide is used as dye to detect the DNA fragments separated by gel electrophoresis.