Molecular Machine -- "Flying Saucer Carrying Two Warheads" -- Could Help Fight Bacterial Infections
A news item at Science Daily, "New Recruits in the Fight Against Disease: Anti-Bacterial 'Killing Machine' Deciphered," describes how studying the inner workings of bacteria-killing molecular machines could lead to new methods of treating infections. As the article states:
"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," Dr. [Sheena] McGowan said.The technical paper in Proceedings of the U.S. National Academy of Sciences puts it this way:
"It operates by locking onto the bacterial surface using eight separate docking sites located on one face of the saucer. The two warheads can then chew through the surface of the cell, rapidly killing the bacteria."
Associate Professor [Ashley] Buckle said the PlyC, which attacks the streptococci bacteria, was a very promising target for the future development of new drugs.
Bacteriophages deploy lysins that degrade the bacterial cell wall and facilitate virus egress from the host. When applied exogenously, these enzymes destroy susceptible microbes and, accordingly, have potential as therapeutic agents. The most potent lysin identified to date is PlyC, an enzyme assembled from two components (PlyCA and PlyCB) that is specific for streptococcal species. Here the structure of the PlyC holoenzyme reveals that a single PlyCA moiety is tethered to a ring-shaped assembly of eight PlyCB molecules.According to Professor Buckle in the Science Daily article, the "PlyC, in its purified form, has been shown to be 100 times more efficient at killing certain bacteria than any other lysin to date -- even faster than household bleach."
(Sheena McGowan et al., "X-ray crystal structure of the streptococcal specific phage lysin PlyC," Proceedings of the U.S. National Academy of Sciences, Vol. 109 (31): 12752-57 (July 31, 2012).)
So this is yet another example of natural biological structures significantly outperforming humanity's best efforts, to an extent that it might potentially be enlisted to improve our own technology. As our knowledge deepens, the idea that nature reflects no design simply gets harder and harder for Darwinian evolutionary proponents to defend.