Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Loss of a universal tRNA feature reported

09.02.2007
Scientists at the Virginia Bioinformatics Institute (VBI) report in the Journal of Bacteriology that two alphaproteobacteria lack the universal extra guanylate nucleotide typically found in the transfer RNA molecule tRNAHis.

tRNAs are the molecules responsible for decoding sequence information specified by messenger RNA molecules, information which is ultimately encoded by the DNA template.

tRNAHis is the specific tRNA that assists in incorporating the amino acid histidine into new proteins. Histidine residues make essential contributions to protein structure as well as the catalytic mechanisms of enzymes and must be reliably incorporated during the process of translation.

Until now, bacterial, archaeal, and eukaryotic tRNAs have always been found with an extra guanylate residue at the 5' end of the tRNA molecule. The scientists, led by Kelly Williams of VBI, have shown that tRNAs carrying the amino acid histidine in the alphaproteobacteria Sinorhizobium meliloti and Caulobacter crescentus apparently lack the universal guanylate residue.

... more about:
»RNA »alphaproteobacteria »guanylate »tRNA »tRNAHis

Kelly Williams, research investigator at VBI, remarked: "The loss of a universal and apparently ancient tRNA feature in two members of the alphaproteobacteria was particularly surprising as it represents a radical departure from previously known identity rules for the histidine-carrying tRNAs." He added: "This result implies that tRNA recognition by the enzyme adding histidine to tRNA differs considerably from similar enzymes in other organisms. We have indeed been able to detect an impact on particular regions of the histidyl-tRNA synthetase that are critical for recognizing tRNA."

The researchers used bioinformatic tools such as a computer script – specifically written by the group – to probe the tRNA genes in the alphaproteobacteria group. Examination of the corrected tRNAHis sequences revealed that a group of alphaproteobacteria fails to encode a G (guanylate) at the -1 position of the tRNA as all other bacteria do. Amplification and tRNA sequencing approaches were used to confirm the findings.

Sinorhizobium meliloti and Caulobacter crescentus are members of the alphaproteobacteria, a group of diverse organisms whose members have successfully adopted different lifestyle and energy-yielding strategies in the course of evolution. The organisms are members of a specific group of alphaproteobacteria that comprises the Rhizobiales, Rhodobacterales, Caulobacterales, Parvularculales and Pelagibacter.

Dieter Söll, Sterling Professor of Molecular Biophysics and Biochemistry in the Department of Molecular Biophysics and Biochemistry at Yale University, commented: "The observed absence of the extra guanylate in tRNAHis is a unique case of divergence from a highly conserved ancient tRNA recognition mechanism by an aminoacyl-tRNA synthetase. It will be of special interest to examine if the loss of this tRNA feature has resulted from the presence of an RNase P enzyme that is no longer capable of catalyzing abnormal cleavage at the -1 position in the tRNAHis precursor. It will also be revealing to see how different aminoacyl-tRNA synthetases have adapted to discriminate between their cognate or related substrates and the now less distinctive tRNAHis."

Barry Whyte | EurekAlert!
Further information:
http://vwww.vt.edu

Further reports about: RNA alphaproteobacteria guanylate tRNA tRNAHis

More articles from Life Sciences:

nachricht Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory

nachricht Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>