Scientists have discovered an unknown part of our immune system. It could be important in helping our body fight disease. The researchers are from a science institute in Israel. Dr Yifat Merbl told the BBC the discovery "could provide an untapped source of natural antibiotics". She wrote in a journal: "These findings pave the way for previously undescribed diagnostic and therapeutic strategies in the fight against infectious diseases." The "new" part of the immune system is from a bodily function that recycles proteins. It is capable of producing chemicals that can kill bacteria and viruses.

The researchers focused on peptides. These are amino acid compounds that keep our immune system strong. The scientists said peptides could provide "therapeutic interventions in infectious diseases and immune-compromised conditions". Peptides help to create defences against bacteria and halt their growth. Dr Merbl said: "We discovered a novel mechanism of immunity that is allowing us to have a defence against bacterial infection." She added: "It's happening throughout our body, in all the cells, and generates a whole new class of potential natural antibiotics."