Scientists have discovered a previously unknown part of our immune system. They say their discovery could be important in helping our body fight diseases. The researchers are from the Weizmann Institute of Science in Israel. Professor Yifat Merbl told the BBC that her team's finding "could provide an untapped source of natural antibiotics". The team wrote in the journal "Nature": "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. The scientists say it is capable of producing a multitude of chemicals that can kill bacteria and viruses.

The researchers focused on peptides in their study. These are compounds that consist of two or more amino acids that help to keep our immune system strong. The scientists wrote that peptides could provide "biotechnological applications and therapeutic interventions in infectious diseases and immunocompromised conditions". Peptides help the immune system to create defences against bacteria and help to halt their growth. Professor 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."