Scientists have discovered the structure and operating procedures of a powerful anti-bacterial killing machine that could become an alternative to antibiotics.The bacteriophage-encoded lysin, PlyC, kills a large spectrum of bacteria --- species that can cause symptoms ranging from sore throats to pneumonia and streptococcal toxic shock syndrome. First identified in 1925, PlyC was purified in the 1960s by Professor Fischetti, but its atomic structure proved elusive until now.
Bacteriophages, viruses that specifically infect and kill bacteria using special proteins called lysins, have been investigated as possible treatments since 1919. However, with the discovery of antibiotics in the 1940s, 'phage therapy' was generally abandoned. Because of multi-resistancy development against many antibiotics, there is renewed interest in phage-encoded lysins.
PlyC is actually made from nine separate protein 'parts' that assemble to form a very effective bacterial killing machine. It actually resembles a flying saucer carrying two warheads. It operates by locking onto the bacterial surface using eight separate docking sites located on one face of a flying saucer-like structure. The two warheads can then chew through the surface of the cell, rapidly killing the bacteria.