It may be a right-handed world, but recent Purdue University research indicates that the first building blocks of life were lefties – and suggests why, on a molecular level, all living things remain southpaws to this day.
This schematic illustrates Cooks theory of how serine, one of the 20 amino acids that comprise all living things, may have determined the chirality of other biological molecules at the dawn of evolution. "Left-handed" serine, shown here as L-serine, has virtually the same properties as "right-handed" D-serine. But because of an unknown process that possibly caused L-serine to become more prevalent than D-serine in the environment, the strong clusters that L-serine forms bonded only with other left-handed amino acids and right-handed sugars. Other biological molecules with an incompatible chirality were left out of the bonding process, and all the organisms on the planet eventually developed from amino acids with exclusively left-handed chirality.
For higher resolution graphic klick here
In findings that may shed light on the earliest days of evolutionary history, R. Graham Cooks and a team of Purdue chemists have reported experiments that suggest why all 20 of the amino acids that comprise living things exhibit "left-handed chirality," which refers to the direction these basic biological molecules twist–and how a single amino acid might be the reason.
Amino acids can be oriented either to the left or the right and possess the same chemical properties regardless of their chirality. But somewhere along the line, living things evolved using only amino acids of the left-handed variety. Scientists have puzzled over the reason for many years, but Cooks’ group seems to have found the answer: A single amino acid called serine set the standard eons ago, forcing all other biological molecules to follow suit.
Chad Boutin | Purdue University
Colorectal cancer risk factors decrypted
13.07.2018 | Max-Planck-Institut für Stoffwechselforschung
Algae Have Land Genes
13.07.2018 | Julius-Maximilians-Universität Würzburg
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
13.07.2018 | Event News
13.07.2018 | Materials Sciences
13.07.2018 | Life Sciences