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 A Map of the Cell’s Power Station
18.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht On the way to developing a new active ingredient against chronic infections
18.08.2017 | Deutsches Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>