Two University of California at Davis surgeons have been banned from doing human research after they injected bacteria into the head wounds of consenting terminally ill patients without university authorization, according to a letter sent from the school to the U.S. Food and Drug Administration.The university ordered Drs. J. Paul Muizelaar and Rudolph J. Schrot to immediately "cease and desist" doing the procedure last fall, according to the letter, dated Oct. 17, 2011, obtained by theSacramento Bee.Chancellor Linda P.B. Katehi has ordered a review into the actions of Muizelaar, who is chairman of the department of neurological surgery at U.C. Davis, and Schrot, an assistant professor.The lack of approval before conducting human research could jeopardize the school's federal funding, said Rosamond Rhodes, director of bioethics education at the Mount Sinai School of Medicine."You are required to comply with federal rules if you are an institution accepting federal funding for research," she said. "Whether or not the project is funded by the federal government, it still has to comply with the rules."A spokesperson for the FDA told ABCNews.com it "cannot confirm nor deny the existence of an investigation."The surgeons said they were given consent by three terminal patients with glioblastomas, tumors that arise from the supportive tissue of the brain, to insert bacteria into their head wounds. The doctors believed the bacteria would create a postoperative infection that could help the patients live longer, according to documents included in the letter to the FDA.The surgeons insisted they were conducting an innovative treatment, not research."There are people who blatantly break the rules that endanger all of their research programs. We certainly didn't blatantly trample any rules," Muizelaar told the Sacramento Bee.Two of the patients contracted sepsis and died as a result of the procedure, according to the university.Harris A. Lewin, vice chancellor for research, wrote that the experimental procedure, which had been conducted on three patients without university or FDA permission, "constituted serious and continuing noncompliance reportable to the FDA."Muizelaar was ordered to hand off his clinical investigations, while Schrot was required to take the FDA's Clinical Investigator Training Course "to assure he possesses requisite knowledge to perform future studies, if and as permitted," the letter stated.On Thursday, the California Institute for Regenerative Medicine awarded the university $53 million for research into Huntington's disease, limb ischemia and osteoporosis.