There's More Than One Way To Skin A Bacterium
A year and a half ago Glenn Reynolds reported on research to use peptide nanotubes to:
"...kill bacteria by punching holes in the bacteria's membrane." You might think of these as a sort of mechanical antibiotic...."By controlling the type of peptides used to build the rings, scientists are able to design nanotubes that selectively perforate bacterial membranes without harming the cells of the host... In theory, these nano-bio agents should be far less prone than existing antibiotics to the development of bacterial resistance."
It is hard to imagine a genetic mutation that would allow bacteria to survive a punctured cell membrane.
Today, Wired News reports that Oculus Innovative Sciences is now producing a liquid called Microcyn that kills even drug resistant bacteria.
According to Hoji Alimi, founder and president of Oculus, the ion-hungry water creates an osmotic potential that ruptures the cell walls of single-celled organisms, and out leaks the cell's cytoplasm. Because multicellular organisms -- people, animals, plants -- are tightly bound, the water is prevented from surrounding the cells, and there is no negative impact.
Though I'm not sure why, Microcyn also is effective against viruses and spores. And unlike with nanotubes, there is no concern with environmental impact.
This is not a pie in the sky development. Oculus has announced FDA 510K clearance of Microcyn technology.
Dermacyn™ Wound Care, the first Microcyn™ Technology product for human use in the United States, will be available to physicians in June 2005 by phoning 1(800) 759-9305.
IMPORTANT UPDATE: Derek Lowe emailed Glenn Reynolds the following:
Had a look at that Speculist/Wired News piece, followed by a perusal of the Oculus web site. Not too many details there for a chemist, so I searched for their IP, and found their patent WO03048421, which shows up assigned to Oculus in its European filing. That gave me more to go on.
I'm not all that impressed. This seems to have very little relation to the nanotube punctures that you wrote about a few months ago, despite the Speculist lead-in, and the Oculus PR doesn't make much sense, either. Their statement in the Wired article is:
the ion-hungry water creates an osmotic potential that ruptures the cell walls of single-celled organisms, and out leaks the cell's cytoplasm. Because multicellular organisms -- people, animals, plants -- are tightly bound, the water is prevented from surrounding the cells, and there is no negative impact
Which is semi-gibberish. Talking about "ion-hungry" water that kills through osmosis makes it sound like it's some sort of ultrapure stuff, but their water has plenty of ions in it, since the electrolysis that produces it makes hypochlorous acid, hydrochloric acid, and so on. Those are surely the source of its bacteria-killing properties, which would then be done through good ol' toxic chemistry. And that "tightly bound" stuff isn't too compelling, either - so it'll just mess up your cells that it can get to, is my take on that, and won't touch bacteria that are embedded in a matrix or biofilm.
And the possibility for dosing this stuff in vivo is zero, by the way, for those same reasons.
Not to be overly defensive, but the title to this post is "More Than One Way To Skin A Bacterium." Of course there is no relation to what Glenn reported in 2003 and Microcyn, EXCEPT that both developments would work by breaching the cell membranes of bacteria while leave the cells of the body untouched. Literally two methods to skin a bacterium. Get it?
What is curious about the Oculus claim (and this should have raised some doubt with me earlier) is that this fluid is said to be effective against viruses. Okay, but by what mechanism? Viruses don't have cell casings.
I'm not ready to write off the Oculus fluid as snake oil yet. But I'll be careful in my enthusiasm.