Bacteriophage

Bacteriophage: A virus that lives within a bacteria. Bacteriophages (called phages, for short) have been very important and heuristic (informative) in bacterial and molecular genetics. Bacteriophages were studied by (among others) Alfred Hershey, Max Delbruck and Salvador Luria who discovered that viruses could exchange genetic material. Hershey and a graduate student Martha Chase at the Cold Spring Harbor Laboratory found that nucleic acid alone could cause viral replication and transmit genetic information. The classic Hershey and Chase experiment provided some of the key proof that genes were, indeed, made of DNA. The "phage group" (Hershey, Delbruck and Luria) went on to share the 1969 Nobel Prize for Physiology or Medicine for their discoveries concerning "the replication mechanism and the genetic structure of viruses." Delbruck died in 1981, Luria in 1991, and Hershey in 1997. The famous "phage group" is thus gone but their legacy and that of the bacteriophages lives on.