An attempt has been made to combine small-angle scattering of X-rays or neutrons with scanning electron microscopy in reciprocal space, in order to establish a structural analysis method covering a wide range of sizes from micro- to macro-scales.

This article describes rational strategies for the optimization of crystal growth using precise in situ control of the temperature and chemical composition of the crystallization solution through dialysis, to generate crystals of the specific sizes required for different downstream structure determination approaches.

The synthesis, characterization and study of structures from a series of bi­phenyls substituted at positions 3, 3', 4 and 4' with groups connected to the bi­phenyl core through oxygen atoms are presented here. The molecular conformation is extensively studied both in the solid as well as in the liquid state, and the effect of different actors (such as packing and chain length) on the torsion angle between aromatic rings is analyzed.

In the title compound, {[Cu(C14H8O4)(C11H10N4O)(H2O)]·1.25H2O}n, the CuII cations are coordinated in a square-pyramidal fashion by trans carboxylate O-atom donors from two diphenate (dip) ligands, trans pyridyl N-atom donors from two bis(4-pyridyl)urea (bpu) ligands, and a ligated water molecule in the apical position. [Cu(H2O)(dip)(bpu)]n coordination polymer layer motifs are oriented parallel to (overline{1}02). These layer motifs display a standard (4,4) rectangular grid topology and stack in an AAA pattern along the a-axis direction to form the full three-dimensional crystal structure of the title compound, mediated by N—H...O and O—H...O hydrogen bonding patterns involving the water molecules of crystallization.

The crystal structure of haemoglobin from Atlantic cod has been solved to 2.54 Å resolution. The structure consists of two tetramers in the crystallographic asymmetric unit. The structure of haemoglobin obtained from one individual cod suggests polymorphism in the tetrameric assembly.

Endoplasmic reticulum (ER)-associated degradation (ERAD) is a protein quality-control pathway in eukaryotes in which misfolded ER proteins are polyubiquitylated, extracted and ultimately degraded by the proteasome. This process involves ER membrane-embedded ubiquitin E2 and E3 enzymes, as well as a soluble E2 enzyme (Ubc7 in Saccharomyces cerevisiae and UBE2G2 in mammals). E2-binding regions (E2BRs) that recruit these soluble ERAD E2s to the ER have been identified in humans and S. cerevisiae, and structures of E2–E2BR complexes from both species have been determined. In addition to sequence and structural differences between the human and S. cerevisiae E2BRs, the binding of E2BRs also elicits different biochemical outcomes with respect to E2 charging by E1 and E2 discharge. Here, the Schizosaccharomyces pombe E2BR was identified and purified with Ubc7 to resolve a 1.7 Å resolution co-crystal structure of the E2BR in complex with Ubc7. The S. pombe E2BR binds to the back side of the E2 as an α-helix and, while differences exist, it exhibits greater similarity to the human E2BR. Structure-based sequence alignments reveal differences and conserved elements among these species. Structural comparisons and biochemistry reveal that the S. pombe E2BR presents a steric impediment to E1 binding and inhibits E1-mediated charging, respectively.

Cytisine, a natural product with high affinity for clinically relevant nicotinic acetylcholine receptors (nAChRs), is used as a smoking-cessation agent. The compound displays an excellent clinical profile and hence there is an interest in derivatives that may be further improved or find use in the treatment of other conditions. Here, the binding of a cytisine derivative modified by the addition of a 3-(hydroxypropyl) moiety (ligand 4) to Aplysia californica acetylcholine-binding protein (AcAChBP), a surrogate for nAChR orthosteric binding sites, was investigated. Isothermal titration calorimetry revealed that the favorable binding of cytisine and its derivative to AcAChBP is driven by the enthalpic contribution, which dominates an unfavorable entropic component. Although ligand 4 had a less unfavorable entropic contribution compared with cytisine, the affinity for AcAChBP was significantly diminished owing to the magnitude of the reduction in the enthalpic component. The high-resolution crystal structure of the AcAChBP–4 complex indicated close similarities in the protein–ligand interactions involving the parts of 4 common to cytisine. The point of difference, the 3-(hydroxypropyl) substituent, appears to influence the conformation of the Met133 side chain and helps to form an ordered solvent structure at the edge of the orthosteric binding site.

Determining the locations of future highways and roads in countries with tropical rainforests will be the greatest single factor in influencing future forest loss, fragmentation and degradation. In broad terms, roads can be thought of as the enemies of rainforests. By spreading people out across the forest, roads inherently promote rapid and widespread deforestation.

The post Roads kill rainforests. Stop them now, say Smithsonian biologists appeared first on Smithsonian Insider.

Scientists from the Smithsonian Migratory Bird Center at the National Zoo have taken blood samples from thousands of birds and mosquitoes in an effort to track the progress of the West Nile Virus in the eastern United States. Come along in this video as Smithsonian scientists net birds living in downtown Washington, D.C., extract small amounts of blood, and then release them back into the "wild."

The post Video: Common birds in Washington, D.C. are helping Smithsonian scientists track intensity of the West Nile Virus appeared first on Smithsonian Insider.

The National Zoo has been awarded a grant from the U.S. Fish and Wildlife Service to establish a captive population of the Virginia big-eared bat at the National Zoo’s Conservation & Research Center near Front Royal, Va. Only 15,000 Virginia big-eared bats remain living in caves in West Virginia, Virginia, Kentucky and North Carolina, and these are threatened by the white-nose syndrome.

The post In face of crisis, National Zoo to start captive population of Virginia big-eared bats appeared first on Smithsonian Insider.

Invasive species, contaminants, excessive nutrient's and sediment are just some of the many factors threatening sensitive wetlands and seagrass beds.

The post Smithsonian to lead study on degradation of nearshore coastal habitats of the Chesapeake appeared first on Smithsonian Insider.

There are several hypotheses about how amphibian chytrid has spread around the world, but the trade in amphibians for food, bait, pets and laboratory animals has been identified as the most likely mode of spread

The post Trade in frog legs may spread diseases deadly to amphibians appeared first on Smithsonian Insider.

Birds do it. Bees do it. And in a laboratory in northern California, scientists using bumblebees recently figured out the best way to measure it--vertical lift!

The post Laboratory tests reveal precise way to measure vertical lift in bumblebees and other small insects and birds appeared first on Smithsonian Insider.

Eleven bats remain in the National Zoo’s colony. The initial challenge the team faced was how to feed the animals. Virginia big-eared bats, which are a subspecies of the Townsend’s big-eared bat (Corynorhinuss townsendii), eat while flying.

The post Captive colony of Virginia big-eared bats providing valuable lessons in battle against deadly white-nose syndrome appeared first on Smithsonian Insider.

The stars move quickly because they are very close to each other, separated by only about one-fourth the distance from the Earth to the Moon. As a result, they share strong gravitational forces. They were once farther apart but have spiraled closer together over time. Billions of years from now, they will crash together and merge.

The post At 1,500,000 mph, twin stars in the constellation Cancer win speediest orbit award appeared first on Smithsonian Insider.

About as thick as a standard dictionary, this turtle’s shell may have warded off attacks by the Titanoboa, thought to have been the world’s biggest snake, and by other, crocodile-like creatures living in its neighborhood 60 million years ago.

The post Newly discovered prehistoric turtle co-existed with world’s biggest snake appeared first on Smithsonian Insider.

The rescue pods will be part of the project’s Amphibian Rescue Center at Summit Municipal Park, which will also include a lab with a quarantine facility.

The post Shipping industry sends help as project in Panama tackles amphibian crisis appeared first on Smithsonian Insider.

The Smithsonian’s National Zoo celebrated the completion of Phase I of Elephant Trails, an innovative and expanded home for Asian elephants, on Sept. 2. Phase […]

The post Elephant Trails exhibition opens at National Zoological Park appeared first on Smithsonian Insider.

Researchers at the Smithsonian Conservation Biology Institute conducted three different kinds of genetics tests and all yielded the same result—the Galapagos seabirds have been genetically different from the magnificent frigatebirds elsewhere for more than half a million years.

The post Genetic surprise: Magnificent frigatebird living on Galapagos Islands is distinct species appeared first on Smithsonian Insider.

This circa 1910 Yup'ik mask from Good News Bay, Alaska--made of driftwood, baleen, feathers, paint and cotton twine--is part of "Infinity of Nations: Art and History in the Collections of the National Museum of the American Indian," an exhibition at the National Museum of the American Indian, opening Saturday, Oct. 23.

The post Yup’ik mask in “Infinity of Nations” exhibition at the American Indian Museum appeared first on Smithsonian Insider.

The science-based study will evaluate elephant welfare along a quality continuum, assessing the impact of zoo management practices by looking at the elephants’ responses to differences in practices among zoos.

The post Conservation Biology Institute to play role in elephant welfare study appeared first on Smithsonian Insider.

Known as one of the greatest racehorses of his day and sire to more winning horses than any other American thoroughbred before or since, this Smithsonian loan returned the legendary Lexington's remains to the town of his birthplace some 160 years after he was born.

The post One hundred sixty years after his birth a racehorse’s bones return to Lexington appeared first on Smithsonian Insider.

Despite the general perception of exurban development as environmentally preferable to urban sprawl, this is not necessarily correct. Housing development is detrimental for natural bird communities even at low housing levels.

The post Exurban development is changing communities of birds in Eastern Forests appeared first on Smithsonian Insider.

Subjects watched demonstrators for varying amounts of time. When given the pipe, each of the subjects in both groups opened the door on their first attempt using the method they had seen demonstrated.

The post Lemurs exhibit ability for social learning in zoo experiment appeared first on Smithsonian Insider.

Bats living in the dense urban area of Panama City, the scientists learned, represent just a small fraction of the roughly 25 species of high-flying insectivorous bats found in Panama’s rainforests.

The post Only large, fast-flying bats can handle life in the big city; small bats can’t adapt appeared first on Smithsonian Insider.

A new species of Brazilian leaf beetle named Cachiporra extremaglobosa, (which translated means the “extremely globular billy club leaf beetle,”) was recently discovered by scientists at the Smithsonian’s National Museum of Natural History.

The post “Billy club” leaf beetle has been hiding in Smithsonian collections since 1959 appeared first on Smithsonian Insider.

Last week, the Kepler team and CfA astronomers announced the discovery of a system of six transiting planets around one Sun-like star. The previous record holder for the number of transiting planets was three.

The post Six orbiting planets sets record for Sun-like stars say Kepler, Smithsonian astronmers appeared first on Smithsonian Insider.

NASA's Chandra X-ray Observatory has discovered the first direct evidence for a superfluid, a bizarre, friction-free state of matter, at the core of a neutron star.

The post Astronomers detect bizarre superfluid in core of neutron star appeared first on Smithsonian Insider.

For more than three decades JoGayle Howard dedicated her life and work to reproducing endangered species.

The post JoGayle Howard, National Zoological Park pioneer in reproductive biology, dies appeared first on Smithsonian Insider.

Smithsonian scientists report fledgling catbirds in suburban habitats are at their most vulnerable stage of life, with almost 80 percent killed by predators before they reach adulthood. Almost half of the deaths were connected to domestic cats.

The post Alarming number of fledgling, suburban catbirds fall prey to domestic cats, study finds appeared first on Smithsonian Insider.

As researchers investigate the impact of the Burmese python in the Everglades, scientists from the Smithsonian Institution, South Florida Natural Resources Center and the University of Florida examined the snake’s predation of the area’s birds. They found that birds, including endangered species, accounted for 25 percent of the python’s diet in the Everglades.

The post Invasive Burmese pythons are taking a toll on Florida’s native birds appeared first on Smithsonian Insider.

To help regulators and engineers develop and test such treatment systems, and ultimately enforce these standards, a team of researchers developed a statistical model to see how to count small, scarce organisms in large volumes of water accurately.

The post Smithsonian researchers help block ship-borne bioinvaders with new screening strategy appeared first on Smithsonian Insider.

“Our results support the idea that environmental conditions on tropical non-breeding areas can influence the departure time for spring migration,” said Colin Studds, a postdoctoral fellow at the Smithsonian Conservation Biology Institute's Migratory Bird Center and lead author of the study.

The post Smithsonian scientists find declining rainfall is a major influence for migrating birds appeared first on Smithsonian Insider.

The April 5 exhibits, “In the Mummy’s Tomb,” “Making a Mummy” and “What’s in a Face,” focus on Egyptian burial rites.

The post Mummies featured in new Smithsonian exhibition appeared first on Smithsonian Insider.

Sita (SEE-ta), a 2-year-old female clouded leopard at the Smithsonian Conservation Biology Institute in Front Royal, Va., gave birth to these two cubs on Monday, […]

The post Clouded leopard cubs born at Smithsonian Conservation Biology Institute appeared first on Smithsonian Insider.

Astronomers of the future won't have to take the Big Bang on faith. With careful measurements and clever analysis, they can find the subtle evidence outlining the history of the universe.

The post Astronomers in distant future might still deduce the Big Bang origin of the Universe appeared first on Smithsonian Insider.

In addition to the species name, Leafsnap provides high-resolution photographs and information about the tree's flowers, fruit, seeds and bark—giving the user a comprehensive understanding of the specie

The post Leafsnap, a new mobile app that identifies plants by leaf shape, is launched by Smithsonian and collaborators appeared first on Smithsonian Insider.

The National Aeronautics and Space Administration has made available to the public a new online collection of images that capture the excitement of planetary exploration and the journey to understand the origin and evolution of the solar system.

The post Stunning high-resolution NASA images available online for public exhibits appeared first on Smithsonian Insider.

Researchers at the Smithsonian Conservation Biology Institute and partnering organizations will build a frozen repository of Great Barrier Reef coral sperm and embryonic cells. Genetic banks composed of frozen biomaterials hold strong promise for basic and applied research and conservation of species and genetic variation.

The post Smithsonian Conservation Biology Institute to help create frozen repository of sperm and embryonic cells for Great Barrier Reef corals appeared first on Smithsonian Insider.

Five cheetah cubs were born May 28 to 6-year-old Amani at the Smithsonian Conservation Biology Institute in Front Royal, Va. Amani is a dedicated mother according to keepers, who have observed her nursing and grooming the cubs.

The post Five cheetah cubs born at Smithsonian Conservation Biology Institute appeared first on Smithsonian Insider.

Any adventurer, hiker or backyard naturalist with a camera can help scientists survey and hopefully save the world’s amphibians thanks to a new social networking site that links “citizen scientists” with researchers tracking the decline of amphibians around the globe.

The post Scientists turn to social networking and citizen scientists to help keep track of amphibians appeared first on Smithsonian Insider.

The recent field of invasion biology faces a new challenge as 19 eminent ecologists issue a call to "end the bias against non-native species" in the journal Nature.

The post Is ecology biased against non-native species? appeared first on Smithsonian Insider.

Smithsonian scientists have confirmed that chytridiomycosis, a rapidly spreading amphibian disease, has reached a site near Panama’s Darien region. This was the last area in the entire mountainous neotropics to be free of the disease. This is troubling news for the Panama Amphibian Rescue and Conservation Project, a consortium of nine U.S. and Panamanian institutions that aims to rescue 20 species of frogs in imminent danger of extinction.

The post Deadly amphibian disease detected in the last disease-free region of Central America appeared first on Smithsonian Insider.

Some--birds called wire-tailed manakins, residents of tropical forests in the Americas--are cooperators as well as competitors. They cooperate, forming alliances for a common cause.

The post Manakins, birds of tropical forests, form alliances for common good appeared first on Smithsonian Insider.

Scientists and educators from the Smithsonian Conservation Biology Institute and George Mason University broke ground June 29 on a green-design conservation complex that embodies the concept of the living classroom.

The post Smithsonian Conservation Biology Institute and George Mason University expand partnership appeared first on Smithsonian Insider.

A team of scientists have found that because of this, high summer temperatures have been a strong influence in determining bill size in some birds, particularly species of sparrows that favor salt marshes.

The post It’s no sweat for salt marsh sparrows to beat the heat if they have a larger bill appeared first on Smithsonian Insider.

The Life and Morals of Jesus of Nazareth, more commonly known as the Jefferson bible, is a volume created by Thomas Jefferson containing passages he […]

The post Unlocking the mysteries of Jefferson’s bible with high-tech analysis and microscopic testing appeared first on Smithsonian Insider.

For the first time in decades, researchers have found a new bird species in the United States. Based on a specimen collected in 1963 on Midway Atoll, Northwestern Hawaiian Islands, biologists have described a new species of seabird, Bryan’s shearwater

The post Bryan’s shearwater, new Hawaiian seabird species, discovered appeared first on Smithsonian Insider.

The Zoo’s Smithsonian Conservation Biology Institute in Front Royal, Va., is celebrating the recent hatching of two Micronesian kingfisher (Todiramphus c. cinnamominus) chicks, a female and male, born July 25 and Aug. 20, respectively.

The post Zoo celebrates birth of two Micronesian kingfishers, a species extinct in the wild appeared first on Smithsonian Insider.