John Tavis, Ph.D. (IMAGE) Saint Louis University Caption John Tavis, Ph.D., is a professor of molecular microbiology and immunology at Saint Louis University. Credit Saint Louis University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.