Johnson, David A.: - David A. Johnson is a native Tennessean and professor emeritus of biochemistry and molecular biology at Quillen College of Medicine, East Tennessee State University, where he taught medical biochemistry for forty-four years while mentoring graduate students. A lifelong Christian who has published over sixty scientific papers, Johnson and his wife live in Jonesborough, Tennessee, in the beautiful Appalachian Mountains. Search @DrJQuillen for his YouTube channel.