M63 Medium: M63 is a minimal medium used in cultivation of Escherichia coli. Bacteria can grow easily on this medium because the medium contains carbon compounds such as the glucose found in glycerol. Glycerol can serve as both a carbon source and an energy source. Salts are present to supply nitrogen, phosphorus, and trace metals that the bacteria would need for growth1. The addition of magnesium sulfate supplies the magnesium ions that are essential for the enzymatic reaction of DNA replication.