Navigation Links
'Fishy' clue helps establish how proteins evolve
Date:1/27/2009

New Haven, Conn. Three billion years ago, a "new" amino acid was added to the alphabet of 20 that commonly make up proteins in organisms today. Now researchers at Yale and the University of Tokyo have demonstrated how this rare amino acid and, by example, other amino acids made its way into the menu for protein synthesis. The study appeared in the December 31 advance online publication of the journal Nature.

The rare amino acid the Yale researchers studied, pyrrolysine (Pyl), gave the researchers a molecular handle by being an extreme example of an amino acid that evolved to serve a highly specific need.

The amino acid alphabet shapes the language of proteins. When the genetic code was deciphered four decades ago, scientists believed that there were no more than 20 amino acid "letters" that universally meshed with the nucleic acid part of the protein code. But, like many alphabets, the language of proteins has letters with modifications like accent marks that modify their use.

When cells make proteins, a tightly coordinated pair of molecules a tRNA and a tRNA synthetase ensure that the correct amino acid is added in a growing protein chain. These molecules are highly specific for the amino acid they "manage" and are coded directly in the genome. All of the 20 common amino acids are incorporated into proteins in this way. However, only two uncommon amino acids, including Pyl, have been discovered that follow this pattern.

In most cases, an uncommon amino acid in proteins like letters with accent marks results from modification of one of the standard 20 amino acids after it has become part of the protein. Many human proteins are modified in this way, and deficiencies in these modifications are linked to myriad human diseases including cancer, neurodegeneration, and metabolic disorders.

"Pyl turns out to be special because it represents an uncommon amino acid that is incorporated during normal protein synthesis," said Yale postdoctoral fellow and lead co-author Patrick O'Donoghue. "This is the key difference that makes Pyl so interesting and valuable to molecular biologists. It opens the door to engineering the genetic code."

Pyl is so rare that it has been found in only seven organisms. Each of these microbes evolved in an unusual environmental niche and all use methylamines the compounds that make fish smell "fishy" as a source of energy. Sll's research team characterized and crystallized the molecules that "manage" Pyl and created images that show how these molecules have evolved to work together.

"This is the handle we needed to effectively produce an 'expanded' genetic code," said O'Donoghue. "Now we have the ability to directly genetically encode other uncommon amino acids. By doing that, we will be able to isolate the role of particular modifications and to begin to understand their functions and their role in human disease."

"We have found why it is probably not accidental that out of more than 300 amino acids found in natural proteins, only two have been added beyond the standard 20-member amino acid alphabet," said principal investigator Dieter Sll, Sterling Professor of Molecular Biophysics & Biochemistry and professor of chemistry at Yale.

"This work provides a tantalizing glimpse into how proteins have evolved in living cells," said Laurie Tompkins, who oversees protein synthesis grants at the National Institutes of Health's National Institute of General Medical Sciences, which partially supported the work. "The unique way in which the synthetase binds its tRNA substrate is a testament to the ancient roots of this remarkable enzyme."


'/>"/>

Contact: Janet Rettig Emanuel
janet.emanuel@yale.edu
203-432-2157
Yale University
Source:Eurekalert  

Related biology news :

1. Fishy future written in the genes
2. Natural chemical found in broccoli helps combat skin blistering disease
3. Device helps patients survive, regain function til transplant
4. Presence of gene mutation helps guide thyroid cancer treatment
5. CABI helps phase out dangerous pesticide in EU
6. Diet support helps chronic kidney patients
7. Argonne helps China create cleaner Beijing for 2008 Olympics
8. A tiny pinch from a z-ring helps bacteria cells divide
9. Ultraviolet light helps to secure water supply
10. MSU researcher helps develop computer game for Ugandan children recovering from cerebral malaria
11. Handbook helps parents deal with childhood infections
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
'Fishy' clue helps establish how proteins evolve
(Date:3/28/2017)... , March 28, 2017 The ... Hardware (Camera, Monitors, Servers, Storage Devices), Software (Video Analytics, ... Region - Global Forecast to 2022", published by MarketsandMarkets, ... 2016 and is projected to reach USD 75.64 Billion ... and 2022. The base year considered for the study ...
(Date:3/24/2017)... 24, 2017 The Controller General of Immigration from ... Abdulla Algeen have received the prestigious international IAIR Award for the ... Continue Reading ... ... Controller Abdulla Algeen (small picture on the right) have received the IAIR ...
(Date:3/23/2017)... The report "Gesture Recognition and Touchless Sensing Market by Technology (Touch-based ... to 2022", published by MarketsandMarkets, the market is expected to be worth USD ... 2022. Continue Reading ... ... ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... and LAGUNA HILLS, Calif. , Oct. ... Cancer Research, London (ICR) and University ... SKY92, SkylineDx,s prognostic tool to risk-stratify patients with multiple myeloma ... MUK nine . The University of Leeds ... partly funded by Myeloma UK, and ICR will perform the ...
(Date:10/10/2017)... ... 2017 , ... San Diego-based team building and cooking events company, Lajollacooks4u, has ... The bold new look is part of a transformation to increase awareness, appeal to ... period. , It will also expand its service offering from its signature gourmet cooking ...
(Date:10/10/2017)... 10, 2017 International research firm Parks Associates announced ... at the TMA 2017 Annual Meeting , October 11 in ... residential home security market and how smart safety and security products impact ... Parks Associates: Smart Home ... "The residential security market has ...
(Date:10/9/2017)... DIEGO , Oct. 9, 2017  BioTech ... biological mechanism by which its ProCell stem cell ... critical limb ischemia.  The Company, demonstrated that treatment ... amount of limbs saved as compared to standard ... the molecule HGF resulted in reduction of therapeutic ...
Breaking Biology Technology: