Table of contents


Top

Books and Arts

Food for thought p167

Matthew Hartings reviews Using Food to Stimulate Interest in the Chemistry Classroom Edited by Keith Symcox

doi:10.1038/nchem.1876


Top

Blogroll

Blogroll: Drops in a bucket p169

John Spevacek

doi:10.1038/nchem.1877


Top

News and Views

Enzyme mechanisms: Flexibility leads to function pp170 - 171

Jianhua Zhao & John L. Rubinstein

doi:10.1038/nchem.1879

ATP synthase is an important enzyme for the storage and release of energy in cells. Ion-mobility mass spectrometry has now been used to study its structure, revealing important mechanistic details about its operation and regulation.

See also: Article by Zhou et al.


Supramolecular polymerization: Living it up pp171 - 173

Frank Würthner

doi:10.1038/nchem.1863

Protein fibril formation is involved in many human diseases and thus has been mechanistically elucidated in the context of understanding — and in turn treating — them. This biological phenomenon has now also inspired the design of a supramolecular system that undergoes living polymerization.

See also: Article by Ogi et al.


Energy transfer: Vibronic coherence unveiled pp173 - 175

Vivek Tiwari, William K. Peters & David M. Jonas

doi:10.1038/nchem.1881

Pigment assemblies with high-efficiency electronic energy transfer have recently been observed to show unusual and persistent coherence, but its origin is not fully understood. Now, a combination of 2D electronic spectroscopy and theoretical modelling has allowed the excitonic coherence signal of a strongly coupled homodimer to be isolated.

See also: Article by Halpin et al.


Uranium extraction: Coordination chemistry in the ocean pp175 - 177

Yi Lu

doi:10.1038/nchem.1880

The amount of uranium in seawater vastly exceeds that in land-based deposits; but separating it from other more abundant metal ions requires high affinity, selectivity — and the ability to deal with an enormous volume of water. Now, two complementary approaches have made considerable contributions to overcoming these challenges.

See also: Article by Zhou et al.


Enzyme catalysis: Basic principles in one easy lesson pp177 - 178

Lawrence T. Scott

doi:10.1038/nchem.1872

Enzymes catalyse nearly all of the myriad chemical reactions that occur in every living organism. An easily understandable, visually appealing model has now been described that illustrates the fundamentals of how enzymes work.

See also: Article by Juríček et al.


Top

Articles

Precision design of ethylene- and polar-monomer-based copolymers by organometallic-mediated radical polymerization pp179 - 187

Anthony Kermagoret, Antoine Debuigne, Christine Jérôme & Christophe Detrembleur

doi:10.1038/nchem.1850

no alt info

Copolymers of ethylene and polar monomers are produced industrially using free radical polymerization that leads to broad molecular weight distributions of products with ill-defined structures. Now, an organo–cobalt complex is shown to control the radical copolymerization of ethylene with polar monomers under mild experimental conditions, and allows access to block-like copolymers with targeted compositions and monomer distributions.


Living supramolecular polymerization realized through a biomimetic approach pp188 - 195

Soichiro Ogi, Kazunori Sugiyasu, Swarup Manna, Sadaki Samitsu & Masayuki Takeuchi

doi:10.1038/nchem.1849

no alt info

Self-organization that occurs far from thermodynamic equilibrium is ubiquitous in nature but has remained challenging to control in synthetic supramolecular systems. A complex system has now been devised that displays such behaviour. Porphyrin derivative monomers undergo living supramolecular polymerization, a reaction underpinned by the interplay of two supramolecular polymerization pathways.

See also: News and Views by Würthner


Two-dimensional spectroscopy of a molecular dimer unveils the effects of vibronic coupling on exciton coherences pp196 - 201

Alexei Halpin, Philip J. M. Johnson, Roel Tempelaar, R. Scott Murphy, Jasper Knoester, Thomas L. C. Jansen & R. J. Dwayne Miller

doi:10.1038/nchem.1834

no alt info

The observation of long-lived coherent oscillations in the nonlinear spectra of photosynthetic proteins has raised significant discussion on the role of quantum effects in biology. Using a model system, the signatures of inter-exciton coherence have been isolated, which has allowed the influence of vibronic coupling to be studied in unprecedented detail.

See also: News and Views by Tiwari et al.


Photocurrent generation based on a light-driven proton pump in an artificial liquid membrane pp202 - 207

Xiaojiang Xie, Gastón A. Crespo, Günter Mistlberger & Eric Bakker

doi:10.1038/nchem.1858

no alt info

Light-driven proton pumps are used in biology to create a proton gradient that can be subsequently converted into chemical energy. Here, an artificial light-harvesting system based on a membrane doped with a spiropyran is described. Irradiation with UV light generates a proton flux across the membrane and results in the generation of an electrical current.


Ion mobility–mass spectrometry of a rotary ATPase reveals ATP-induced reduction in conformational flexibility pp208 - 215

Min Zhou, Argyris Politis, Roberta B. Davies, Idlir Liko, Kuan-Jung Wu, Alastair G. Stewart, Daniela Stock & Carol V. Robinson

doi:10.1038/nchem.1868

no alt info

Ion mobility–mass spectrometry has enabled the study of conformation and dynamics of membrane proteins in the gas phase. Here, the enhanced flexibility of macromolecular ATPase was investigated by comparing arrival time distributions of distinct species and relating them to different solution conditions, leading to the proposal of a nucleotide-triggered regulatory mechanism.

See also: News and Views by Zhao & Rubinstein


State-resolved diffraction oscillations imaged for inelastic collisions of NO radicals with He, Ne and Ar pp216 - 221

Alexander von Zastrow, Jolijn Onvlee, Sjoerd N. Vogels, Gerrit C. Groenenboom, Ad van der Avoird & Sebastiaan Y. T. van de Meerakker

doi:10.1038/nchem.1860

no alt info

When molecules collide with atoms or other molecules their quantum mechanical character can lead to the diffraction of matter waves. Making use of advances in molecular beam technology, such diffraction oscillations have now been observed with unprecedented sharpness and angular resolution in the benchmark NO + He, Ne, or Ar systems.


Induced-fit catalysis of corannulene bowl-to-bowl inversion pp222 - 228

Michal Juríček, Nathan L. Strutt, Jonathan C. Barnes, Anna M. Butterfield, Edward J. Dale, Kim K. Baldridge, J. Fraser Stoddart & Jay S. Siegel

doi:10.1038/nchem.1842

no alt info

Enzymatic catalysis relies on stereoelectronic complementarity between the enzyme's active site and the substrate's transition state. A simple model system illustrating this tenet has now been devised. The bowl-to-bowl inversion of corannulene, catalysed inside the cavity of a synthetic receptor by an induced-fit mechanism, arises from ground-state destabilization combined with transition-state stabilization.

See also: News and Views by Scott


Conversion of light into macroscopic helical motion pp229 - 235

Supitchaya Iamsaard, Sarah J. Aßhoff, Benjamin Matt, Tibor Kudernac, Jeroen J. L. M. Cornelissen, Stephen P. Fletcher & Nathalie Katsonis

doi:10.1038/nchem.1859

no alt info

Helices are found at every level of natural systems, where their dynamic potential is exploited to achieve a variety of functions. Here, liquid-crystalline molecular switches embedded in a polymer are used to prepare biomimetic spring-like materials that can convert molecular motion into macroscopic work.


A protein engineered to bind uranyl selectively and with femtomolar affinity pp236 - 241

Lu Zhou, Mike Bosscher, Changsheng Zhang, Salih Özçubukçu, Liang Zhang, Wen Zhang, Charles J. Li, Jianzhao Liu, Mark P. Jensen, Luhua Lai & Chuan He

doi:10.1038/nchem.1856

no alt info

The extraction of uranium from seawater is limited by the high concentrations of carbonate and competing metal ions. Now, a highly selective uranyl-binding protein with femtomolar affinity has been developed. This protein can extract up to 60% uranium from synthetic seawater when immobilized on bacterial cell surfaces or amylose resin.

See also: News and Views by Lu


Dye-sensitized solar cells with 13% efficiency achieved through the molecular engineering of porphyrin sensitizers pp242 - 247

Simon Mathew, Aswani Yella, Peng Gao, Robin Humphry-Baker, Basile F. E. Curchod, Negar Ashari-Astani, Ivano Tavernelli, Ursula Rothlisberger, Md. Khaja Nazeeruddin & Michael Grätzel

doi:10.1038/nchem.1861

no alt info

A dye that both maximizes electrolyte compatibility and improves light-harvesting properties has been designed for dye-sensitized solar cells. In cells based on the cobalt(II)/(III) redox mediator, use of the dye resulted in a power-conversion efficiency of 13%, revealing the great potential of porphyrin dyes for future solar cell applications.


Building an appropriate active-site motif into a hydrogen-evolution catalyst with thiomolybdate [Mo3S13]2− clusters pp248 - 253

Jakob Kibsgaard, Thomas F. Jaramillo & Flemming Besenbacher

doi:10.1038/nchem.1853

no alt info

Non-noble-metal-based MoS2 nanostructures are hydrogen evolution catalysts whose active sites are known to be located at the edges. Supported thiomolybdate [Mo3S13]2− nanoclusters have now been prepared that exhibit a structural motif similar to that of MoS2 edges. The nanoclusters, synthesized by a scalable route, demonstrate a high turnover frequency.


Top

In Your Element

The A–Z of zirconium p254

John Emsley

doi:10.1038/nchem.1875

From fake gems to a fixture of nuclear plants, John Emsley considers the many uses of zirconium.


Top