Antibiotic resistance in pathogenic bacteria is a growing global challenge. Danish researchers have now discovered that bacteria use a code language to avoid being controlled. Understanding this code language will be paramount to developing new antibiotics in the future.
Pathogenic bacteria -- such as those that cause tuberculosis and typhoid fever -- use a variety of clever tricks against our immune system and the antibiotics we use to control them.
One of these tricks is the ability to go "under cover" and hide from the immune system and the treatment by going into a dormant state where they are not discovered. For several years, researchers at Aarhus University have studied the molecular mechanisms that enable bacteria to hide in this way, and new research now suggests that they also make use of code language in their attempt to avoid being controlled.
The results have just been published in the journal Nucleic Acids Research, and include detailed three-dimensional structures of specific cell toxins that are activated during treatment with for example antibiotics, and demonstrate what happens to them when they bind to specific regions of the DNA of the bacterial cells. The toxins are usually kept in check by their partners, the so-called "anti-toxins," and the researchers have discovered that the palindrome codes enable the anti-toxins to block two toxins at the same time. The amino acid sequence of the codes fits as a key in a lock, and the palindromic sequence is necessary because the two toxins to be blocked are rotated 180 degrees relative to each other.
Kirstine L. Bendtsen, Kehan Xu, Majbritt Luckmann, Kristoffer S. Winther, Shiraz A. Shah, Christian N. S. Pedersen, Ditlev E. Brodersen. Toxin inhibition in C. crescentus VapBC1 is mediated by a flexible pseudo-palindromic protein motif and modulated by DNA binding. Nucleic Acids Research, 2016; gkw1266 DOI: 10.1093/nar/gkw1266
Posted by Dr. Tim Sandle