Bacterial research. Technician plating a petri dish with bacteria in an anaerobic chamber. This technique is used for antibiotic tests on bacteria which exist without oxygen. A number of bacteria species live in anaerobic environments, including in the human intestines. Some bacteria have adapted so well to an anaerobic existence that they are killed if brought into contact with oxygen. Antibiotic research is required because some organisms in a bacterial population have a resistance to a particular type of antibiotic. They will pass this resistance onto their descendants unless another, effective antibiotic can be found to kill them.