The study, in the journal Structure, reveals that after eons of gradual evolution, proteins suddenly experienced a “big bang” of innovation.
The active regions of many proteins, called domains, combined with each other or split apart to produce a host of structures that had never been seen before. This explosion of new forms coincided with the rapidly increasing diversity of the three superkingdoms of life (bacteria; the microbes known as archaea; and eukarya, the group that includes animals, plants, fungi and many other organisms).
Lead author Gustavo Caetano-Anollés, a professor of bioinformatics in the department of crop sciences at the University of Illinois and an affiliate of the Institute for Genomic Biology, has spent years studying protein structures – he calls them “architectures” – which he suggests offer a reliable record of evolutionary events.
By conducting a census of all the domains that appear in different groups of organisms and comparing the protein repertoires of hundreds of different groups, the researchers were able to construct a timeline of protein evolution that relates directly to the history of life.
“The history of the protein repertoire should match the history of the entire organism because the organism is made up of all those pieces,” Caetano-Anollés said.
He and his co-author, postdoctoral researcher Minglei Wang, were interested in tracing how proteins make use of their domains, or groups of domains, to accomplish various tasks. These domains or domain clusters can be thought of as “modules” that fit together in various ways to achieve different ends.
Unlike the sequence of amino acids in a protein, which is highly susceptible to change, the protein modules found today in living organisms have endured because they perform critical tasks beneficial to the organisms that host them, Caetano-Anollés said.
“These modules are resistant to change, they are highly integrated and they are used in different contexts,” he said.
By tracing the history of the modules, the researchers were able to build a rough timeline of protein evolution. It revealed that before the three superkingdoms began to emerge, most proteins contained only single domains that performed a lot of tasks.
“As time progressed, these domains started to combine with others and they became very specialized,” Caetano-Anollés said. This eventually led to the big bang of protein architectures.
“Exactly at the time of the big bang,” many of the combined domains began to split apart, creating numerous single-domain modules again, he said. But these new modules were much more efficient and specialized than their ancient predecessors had been.
“This makes a lot of sense,” Caetano-Anollés said. “As you become more complex, you would want to fine-tune things, to do things in a more tailored way.”
The protein modules of the three superkingdoms also began to diverge more dramatically from one another, with the eukarya (the group that includes plants and animals) hosting the greatest diversity of modules.
“This explosion of diversity allowed the eukarya to do things with their proteins that other organisms could not do,” Caetano-Anollés said.
Diana Yates | University of Illinois
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