I’ve written so many times about antibiotic resistance (among them  yesterday) that you must get tired of it.  Except, it is crucial that we have viable antibiotics to keep our population from succumbing to routine infections.

And, now, Dr. Ailong Ke and her graduate student Robert Battaglia (both from Cornell) and Jason Grieg (UBC- University of British Columbia) have published in Nature Structural and Molecular Biology an intriguing article.  The title may not quite make it clear for you- Structural basis for tRNA decoding and aminoacylation sensing by T-box riboregulators.  

Let me decode that for you.

First, a little basic microbiology.  Aminoacylated tRNA’s (transfer RNA’s, often abbreviated as aa-tRNA) are required to maintain cell viability.   These aa-tRNA are essential, providing ‘house-keeping’ services for the cell; they ‘charge’ amino acids and their respective transfer RNA’s (tRNA) to produce proteins.  (That means both the tRNA and its corresponding amino acid).

A T-box (sometimes called a T-box Leader) is a place (usually found in gram-positive bacteria, in which they control essential genes) where factors (called transcription factors) mediate (or control) the bacterial responses to amino acid starvation.   Gene expression is regulated by the ratio of charged and uncharged tRNA in the cell.   When activated, a series of events is triggered that cause the cell to hyper-produce a bunch of proteins.  In other words, the T-box is essential for properly functioning cells.

The T-box has five structural domains.  (I’ll spare you a description of them.)   And, that provides for the bonding of tRNA (transfer RNA that marshals amino acids from within the cytoplasm to the ribosome of a cell; the ribosome is where the proteins are produced) with amino acids.  The researchers found that two of the domains are necessary for aminoacylation sensing- which means that amino acid production is elevated.   (X-ray crystallography was the scientific process use to demonstrate these facts.  This paper describes the T-box and tRNA complex.)

Now, the goal of the researchers is to find how to preclude this T-box binding.

Why is that so cool?  Since we humans don’t have T-boxes, any toxic process we develop to stop the microbes from binding these amino acids means we have a great method to stop these specific microbes from infecting us, from causing us harm.

 

Except, Gram negative microbes- the ones that don’t always have the T-boxes- are the microbes generally more resistant to antibiotics.  (Gram negative microbes have a “thick” cell wall, Gram positive bacteria lack that extra structure.)

But, it’s a start.