Some bacteria are naturally resistant to certain types of antibiotics. However, some mutate to either produce enzymes that ‘deactivate’ antibiotics, while other mutations change or close the target area on the bacteria that the antibiotic would normally attack. Some even create mechanisms to push the antibiotic back out of the cell when it attacks. Bacteria can acquire antibiotic resistance genes from other bacteria in several ways. They can transfer genetic material through a simple mating process (conjugation), or through plasmid transfer that can ‘reprogramme’ other bacteria to be resistant to antibiotics. They can also pick up stray DNA in their environment or can be infected by viruses, which transmit the resistance gene.