Comments on: Bacteria Evade Antibiotics by Going Incognito

By: T. Dougherty

T. Dougherty — Tue, 03 May 2011 17:02:44 +0000

This builds on work that goes all the way back into the mid-1980′s conducted by the late Harris Moyed. He was the first to show that there was a genetic basis for bacterial persistance with the discovery of the hipAB genes. This was the first of several toxin-antitoxin pairs discovered.

By: Phil Harriman

Phil Harriman — Sun, 01 May 2011 23:23:54 +0000

One bacterial toxin-antidote pair has been explained as a kind of selfish DNA. E. coli Bacteriophage P1 encodes a restriction nuclease and a methylase that protects the host from the nuclease when the phage is acquired as a cytoplasmic prophage. Occasionally a copy of the prophage doesn’t make it into a daughter cell. Those cells can outcompete the bacteria still carrying the prophage. However, the methylase activity dilutes out faster than the nuclease activity as the cells divide, eventually leading to destruction of the DNA of the cells that have lost the prophage.
It looks like the prophage isn’t completely selfish in that the restriction-modification system can protect its host cell (and itself) from foreign DNA that could infect the cell.

By: Ajay

Ajay — Sun, 01 May 2011 07:02:01 +0000

Well, that’s something interesting. Hope we make ‘Future drugs’ soon