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<jats:title>Coolly Disordered</jats:title> <jats:p> Generally speaking, at higher temperature phases materials are more disordered—for example, when solids melt to form liquids. In some cases, however—for example, under high pressure—a more disordered phase can emerge upon cooling. <jats:bold> Schöll <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="303" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1189106">303</jats:related-article> ) now show that an organic molecule, a naphthalene derivative, adsorbed on a silver surface disorders upon cooling below room temperature. This process is driven by the surface bond becoming stronger upon cooling and preventing weaker interactions that allow ordering between molecules in the plane. </jats:p>

<jats:title>Biocatalytic Boost</jats:title> <jats:p> Enzymes tend to direct reactions toward specific products much more selectively than synthetic catalysts. Unfortunately, this selectivity has evolved for cellular purposes and may not promote the sorts of reactions chemists are seeking to enhance (see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="5989" page="285" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1192224">Lutz</jats:related-article> </jats:bold> ). <jats:bold> Siegel <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="309" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1190239">309</jats:related-article> ) now describe the design of enzymes that catalyze the bimolecular Diels-Alder reaction, a carbon-carbon bond formation reaction that is central to organic synthesis but unknown in natural metabolism. The enzymes display high stereoselectivity and substrate specificity, and an x-ray structure of the most active enzyme confirms that the structure matches the design. <jats:bold> Savile <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="305" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1188934">305</jats:related-article> , published online 17 June) applied a directed evolution approach to modify an existing transaminase enzyme so that it recognized a complex ketone in place of its smaller native substrate, and could tolerate the high temperature and organic cosolvent necessary to dissolve this ketone. This biocatalytic reaction improved the production efficiency of a drug that treats diabetes. </jats:p>

<jats:title>Biocatalytic Boost</jats:title> <jats:p> Enzymes tend to direct reactions toward specific products much more selectively than synthetic catalysts. Unfortunately, this selectivity has evolved for cellular purposes and may not promote the sorts of reactions chemists are seeking to enhance (see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="5989" page="285" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1192224">Lutz</jats:related-article> </jats:bold> ). <jats:bold> Siegel <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="309" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1190239">309</jats:related-article> ) now describe the design of enzymes that catalyze the bimolecular Diels-Alder reaction, a carbon-carbon bond formation reaction that is central to organic synthesis but unknown in natural metabolism. The enzymes display high stereoselectivity and substrate specificity, and an x-ray structure of the most active enzyme confirms that the structure matches the design. <jats:bold> Savile <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="305" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1188934">305</jats:related-article> , published online 17 June) applied a directed evolution approach to modify an existing transaminase enzyme so that it recognized a complex ketone in place of its smaller native substrate, and could tolerate the high temperature and organic cosolvent necessary to dissolve this ketone. This biocatalytic reaction improved the production efficiency of a drug that treats diabetes. </jats:p>

<jats:title>Wired</jats:title> <jats:p> Just as there are difficulties in making integrated circuits smaller and faster, barriers are also being reached in the fabrication of wires that connect chips to the motherboard. <jats:bold>Hu and Yu</jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="313" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1190496">313</jats:related-article> ) describe the directed electrodeposition and bonding of copper and platinum wires via a meniscus delivered from a micropipette containing a deposition solution. Wires could be deposited on a range of substrates and were significantly smaller than those obtained using existing techniques. This approach may be useful for device packaging and might offer new approaches for constructing tailored nanoscale structures. </jats:p>

<jats:title>Cenozoic Tectonics</jats:title> <jats:p> The Basin and Range Province of western North America—exemplified by the alternating mountain ridge and valley landscapes across nearly the entire U.S. state of Nevada—started to form ∼50 million years ago through a series of extensions of the continental crust. Prior to that, massive mountain-building collisions at the boundary between North America and the Pacific Ocean formed a subduction zone and compressed the continent. By combining observations of global subduction zone velocities with numerical modeling, <jats:bold> Schellart <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="316" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1190366">316</jats:related-article> ) demonstrate that the thinning of the subducting portion of the oceanic plate controlled how and when the transition from compression to extension occurred. Even today, where the much smaller remnant oceanic plate continues to slowly subduct below North America in the Pacific Northwest, the width of the slab and not its age controls the velocity of subduction. Indeed, this relation may explain the dynamics of other modern subduction zones, from South America to Japan. </jats:p>

<jats:title>Warming the Deep</jats:title> <jats:p> The coldest ocean waters are located at the bottoms of the major ocean basins, and, because it takes a long time for water to sink from the surface to these regions, they are relatively isolated from the warming trends that are now occurring at shallower depths. However, warming in these deep waters has recently been observed, sooner than anticipated. <jats:bold> Masuda <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="319" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1188703">319</jats:related-article> , published online 24 June) performed computer simulations of ocean circulation and found that internal waves are able to transport heat rapidly from the surface waters around Antarctica to the bottom of the North Pacific, which can occur within four decades, rather than the centuries that conventional mechanisms have suggested. </jats:p>

<jats:title>Red Sea Coral Decline</jats:title> <jats:p> Large, rapid sea surface temperature rises of 1°C or greater typically cause bleaching of corals. <jats:bold> Cantin <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="322" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1190182">322</jats:related-article> ) show that smaller temperature increases also have detrimental effects on corals, dramatically reducing their rates of calcification and skeletal extension. Corals in the Red Sea, where water temperatures have risen by 0.4 to 1°C since the mid-1970s, have declined in skeletal extension by about 30%, and decreased in calcification rates by around 18% since 1998. This finding suggests that we may see an end to coral growth in the Red Sea this century. </jats:p>

<jats:title>The Greater Good</jats:title> <jats:p> Zero-sum games (if I win, then you lose) offer an easily grasped heuristic for all sorts of social interactions, especially those that involve money. For instance, companies may offer to contribute some portion of their revenues to charitable causes as an inducement to customers, but it is generally assumed that these pass-throughs directly diminish the corporate bottom line. <jats:bold> Gneezy <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="325" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1186744">325</jats:related-article> ; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="5989" page="287" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1193044">DellaVigna</jats:related-article> </jats:bold> ) have designed a framework that encourages both customers and companies to contribute toward social goods, and, in field tests, this design increased charitable contributions as well as corporate revenues. </jats:p>

<jats:title>C-Family Oxidase Structure</jats:title> <jats:p> The heme-copper oxidases (HCOs) play a key role in aerobic respiration by coupling oxygen reduction to transmembrane proton pumping to generate electrochemical ion gradients across biological membranes that provide energy for many cellular processes. Based on subunit composition, electron donor, and heme type, the HCOs are divided into three families, of which families A and B have been structurally characterized. <jats:bold> Buschmann <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="327" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1187303">327</jats:related-article> , published online 24 June) now report the crystal structure of the C-family <jats:italic>cbb3</jats:italic> oxidase from <jats:italic>Pseudomonas stutzeri</jats:italic> . The structure suggests a different redox-driven pumping mechanism from A and B HCOs, and gives insight into why C HCOs are catalytically active at low oxygen concentrations. </jats:p>

<jats:title>Too Close to Home?</jats:title> <jats:p> Why are some species common while others are exceedingly rare? Attempts to answer this question have met limited success, particularly in hyperdiverse communities, such as tropical forests. <jats:bold> Comita <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="330" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1190772">330</jats:related-article> , published online 24 June; see the cover) reveal a previously overlooked explanation. A large data set on seedling dynamics of 180 tree species on Barro Colorado Island, Panama, combined with Bayesian statistical techniques, revealed that species abundance is shaped by the degree to which species negatively impact their own regeneration. Rare species regenerated far less well than common species in the proximity of conspecific neighbors, suggesting a mechanism determining the relative abundances of tree species in highly diverse tropical forest communities. </jats:p>