Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

A new control mechanism for genetic code translation discovered in bacteria

15.02.2008
Almost all organisms, from bacteria to human beings, share the same genetic code, a group of universal instructions used to convert DNA or RNA sequences into proteins, the “building blocks” of life.

Identification of the evolutionary differences between the system for the translation of the genetic code in humans and other organisms, such as bacteria in this case, are useful, for example, for the design of new antibiotics. Researchers at the Institute for Research in Biomedicine (IRB Barcelona) have discovered that an essential molecular process, namely the determination of the start of protein synthesis, until now considered to be the same for all living organisms, differs in the bacteria Mycoplasma penetrans, a human pathogen that affects the respiratory tract. M. penetrans affects immuno-depressed patients, such as those infected by the HIV virus and some cancer patients. The results of this study have been published in the latest issue of Molecular Cell.

The leader of the study, Lluís Ribas de Pouplana, researcher at IRB Barcelona and head of the Gene Translation Laboratory, explains, “our work strengthens the theory that many of the components of the initial genetic code, established 3,500 million years ago, have matured separately between distinct branches of evolution: bacteria, archaea and eukaryotes”. The origin of the genetic code is one of the issues in evolution biology in which most questions remain unanswered. “The translation machinery is so complex, so universal and so essential that it is difficult to imagine how it arose and how it has evolved. Thanks to these discoveries, we can observe that the genetic code and the protein translation system are not as universal as once thought and that some of the key components of the translation system appeared much later”, concludes Ribas.

In fact, what these researchers have discovered is a difference in the mechanism used by bacteria to differentiate between methionine and isoluecine, two essential amino acids for protein formation. Specifically, methionine is the amino acid used universally to initiate protein formation.

An excessively large enzyme: a false clue for the discovery
As commonly occurs in science, the discovery of this new mechanism was by chance. The researchers were studying an enzyme called methionine-tRNA-synthetase (MetRS), which is found in all living organisms, but in the Mycoplasma bacteria it has an extension that makes it much larger. “We were studying this enzyme in order to elucidate the function of this extension”, explains Ribas. The function of MetRS in all organisms is to take methionine and attach it to the RNA transcript of methionine in order to tell the cell when it must initiate the formation of a certain protein. This task is complicated because the RNA transcript of isoleucine is practically identical. “We then saw that the Mycoplasma enzyme distinguished between the RNA transcript of methionine and the transcript of isoleucine in a more simple and proficient manner that that observed to date in other organisms”.

The most logical deduction was that the extension on this enzyme was a crucial part of this distinct recognition system. However, when the researchers removed this extension in the laboratory, the choice between the two RNA transcipt continued to operate flawlessly. “We still do now know the function of this extension of the enzyme in Mycoplasma, but in the meantime we have discovered a new mechanism of control in the translation system, which in addition, we have observed is shared by other bacteria”. This discovery contributes to an improved understanding of the evolution of the genetic code and also demonstrates its plasticity. “In my opinion a certain degree of complexity shown by the genetic code is one of the main parameters that determines the point at which organisms begin to evolve”, explains the researcher. The fundamental differences between the metabolism of human pathogens and the human being may represent the key for the development of new therapies to treat infection.

Sònia Armengou | alfa
Further information:
http://www.irbbarcelona.org

Further reports about: Mycoplasma Organisms RNA Translation bacteria enzyme genetic code methionine

More articles from Life Sciences:

nachricht The birth of a new protein
20.10.2017 | University of Arizona

nachricht Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

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...

Im Focus: Breaking: the first light from two neutron stars merging

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....

Im Focus: Smart sensors for efficient processes

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...

Im Focus: Cold molecules on collision course

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...

Im Focus: Shrinking the proton again!

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...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>