<unk>  is a group of facultative or obligate anaerobic bacteria (capable of producing ATP when oxygen is absent or is destroyed in normal oxygen levels) that are able to target cancerous cells in the body, suppress<unk>  growth and survive in the body for a long time even after the infection. When this type of bacteria is administered into the body it migrates to the cancerous tissues and starts to grow, then deploys distinct mechanisms to destroy solid<unk> s. Each bacteria species uses a different process to eliminate the<unk> . Some common<unk>  include Salmonella, Clostridium, Bifidobacterium, Listeria, and Streptococcus. The earliest research of this type of bacteria was highlighted in 1813 when scientists began observing that patients that had gas gangrene, an infection caused by the bacteria Clostridium, were able to have<unk>  regressions.
Tumor-homing bacteria
Carcinogenic bacteria
Multidrug-resistant bacteria
Pathogenic fungus
Multidrug-resistant Gram-negative bacteria
Pathogenic bacteria
Enteric bacteria 
Carcinogenic parasite