Antibiotic lysis of a bacterium. Artwork of an antibiotic drug acting on an Escherichia coli bacterium, causing it to burst (lysis) and lose its DNA. The bacterial cell is at centre (oval). Inside the cell is the nuclear material (purple, coiled). This has been ruptured due to drug action (represented by coloured band at upper right), causing the chromosome material (purple strands) containing DNA to burst from the cell. Uncoiling of the DNA prevents the bacterium from dividing before it dies. The antibiotic drugs include penicillin and cephalosporin antibiotics and are used to treat bacterial infections.