The results of these findings were published in an article titled “Novel One-step Mechanism for tRNA 3’-End Maturation by the Exoribonuclease RNase of Mycoplasma gentialium” in the current issue of the Journal of Biological Chemistry.
Co-authors of the article are Ravi K. Alluri, a pre-doctoral student in the department of biomedical science and Dr. Zhongwei Li, Ph.D., associate professor of biomedical science in FAU’s Charles E. Schmidt College of Medicine.
Li and Alluri explain that every organism lives on the same principle that genes direct the production of proteins. This process depends on a set of small RNAs called tRNAs that carry the building blocks of proteins. A tRNA is produced from its gene initially as a precursor that contains extra parts at each end (5’ and 3’ ends) and sometimes in the middle. These extra parts must be removed through RNA processing before tRNA can work during protein production. The processing of tRNA 5’ end has been known for quite some time and work on this enzyme has received a Nobel Prize. Processing of the 3’ end is much more complicated and has only been revealed in some organisms more recently. Organisms that have nucleus in their cells, including humans, appear to process the 3’ end of tRNA in a similar way. A tRNA must be precisely processed before it can carry a building block for proteins.
“Intriguingly, bacteria appear to process the 3’ end of tRNA very differently,” said Alluri. “And we are still trying to reveal the various enzymes called RNases, which remove the 3’ extra parts of tRNA precursors.”
Some of the RNases cut the RNA in the middle, while others trim the RNA from the 3’ end. Most of the bacterial pathways involve multiple RNases to complete tRNA 3’ processing.
“Knowing how tRNA is processed in different types of bacteria is important not only for understanding how bacteria live, but also for developing novel antibiotics that specifically control bacterial pathogens,” said Li.
One such pathogen is the bacterium Mycoplasma genitalium, which is the second smallest known free-living organism that is thought to cause infertility. Alluri and Li’s current work focuses on this bacterium—its genome only contains about 10 percent of the genes found in other common bacteria. Surprisingly, this bacterium contains none of the known RNases for tRNA 3’ processing and hence it has to use a different RNase to do so.
“What we have discovered with Mycoplasma genitalium is that it uses a completely different RNase called RNase R to process the 3’ end of tRNA,” said Alluri. “RNase R can trim the 3’ extra part of a tRNA precursor to make a ‘functional’ tRNA. It is even smart enough to recognize some structural features in the tRNA and tell where the trimming has to stop without harming the mature tRNA.”
The ability of RNase R to completely remove the 3’ extra RNA bases in a single-step trimming reaction represents a novel mechanism of tRNA 3’ processing. Other mycoplasmas generally have small genomes and likely process tRNA in the same way. Using only one enzyme for this complicated task saves genetic resources for mycoplasmas.
“Importantly, blocking the function of RNase R in mycoplasmas can stop protein production and kill the bacteria, making RNase R an excellent target of new antibiotics for treatment of mycoplasma infection,” said Li.About Florida Atlantic University:
Gisele Galoustian | Newswise Science News
The birth of a new protein
20.10.2017 | University of Arizona
Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research