Pope Benedict XVI has appointed the Nobel laureate Werner Arber, a Protestant, to head the Pontifical Academy of Sciences.
Professor Arber, 81, a Swiss microbiologist, who teaches at the University of Basel, shared a Nobel Prize for Physiology or Medicine in 1978 with American scientists Hamilton Smith and Daniel Nathans, for the discovery and application of restriction enzymes, used in fighting bacterial infection.
He has been a member of the Vatican's scientific academy since May 1981 and is on the board of directors. He will succeed Italian Nicola Cabibbo, who died in August.
The nomination of a non-Catholic head is the first in the history of the academy which was founded in 1603.
About 30 Nobel Prize winners are members of the Academy, which has a staff of more than 80 researchers and studies a range of scientific issues.