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Here we have reported novel polymeric devices to control fluid flow using surface forces and capillary action to facilitate counter-diffusive, on-chip protein crystallization.

The nonstructural protein 3 (NSP3) macrodomain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (Mac1) removes adenosine diphosphate (ADP) ribosylation posttranslational modifications, playing a key role in the immune evasion capabilities of the virus responsible for the coronavirus disease 2019 pandemic. Here, we determined neutron and x-ray crystal structures of the SARS-CoV-2 NSP3 macrodomain using multiple crystal forms, temperatures, and pHs, across the apo and ADP-ribose–bound states. We characterize extensive solvation in the Mac1 active site and visualize how water networks reorganize upon binding of ADP-ribose and non-native ligands, inspiring strategies for displacing waters to increase the potency of Mac1 inhibitors. Determining the precise orientations of active site water molecules and the protonation states of key catalytic site residues by neutron crystallography suggests a catalytic mechanism for coronavirus macrodomains distinct from the substrate-assisted mechanism proposed for human MacroD2. These data provoke a reevaluation of macrodomain catalytic mechanisms and will guide the optimization of Mac1 inhibitors.

Cytochrome c oxidase (CcO) is the terminal enzyme in the electron transfer chain in the inner membrane of mitochondria. It contains four metal redox centers, two of which, Cu

The practice of serial X-ray crystallography (SX) depends on efficient, continuous delivery of hydrated protein crystals while minimizing background scattering. Of the two major types of sample delivery devices, fixed-target devices offer several advantages over widely adopted jet injectors, including: lower sample consumption, clog-free delivery, and the ability to control on-chip crystal density to improve hit rates. Here we present our development of versatile, inexpensive, and robust polymer microfluidic chips for routine and reliable room temperature serial measurements at both synchrotrons and X-ray free electron lasers (XFELs). Our design includes highly X-ray-transparent enclosing thin film layers tuned to minimize scatter background, adaptable sample flow layers tuned to match crystal size, and a large sample area compatible with both raster scanning and rotation based serial data collection. The optically transparent chips can be used both for in situ protein crystallization (to eliminate crystal handling) or crystal slurry loading, with prepared samples stable for weeks in a humidified environment and for several hours in ambient conditions. Serial oscillation crystallography, using a multi-crystal rotational data collection approach, at a microfocus synchrotron beamline (SSRL, beamline 12-1) was used to benchmark the performance of the chips. High-resolution structures (1.3-2.7 A) were collected from five different proteins - hen egg white lysozyme, thaumatin, bovine liver catalase, concanavalin-A (type VI), and SARS-CoV-2 nonstructural protein NSP5. Overall, our modular fabrication approach enables precise control over the cross-section of materials in the X-ray beam path and facilitates chip adaption to different sample and beamline requirements for user-friendly, straightforward diffraction measurements at room temperature.

Catalyzing life-sustaining reactions, proteins are composed by 20 different amino acids that fold into a compact yet flexible three-dimensional architecture, which dictates what their function(s) might be. Determining the spatial arrangement of the atoms, the protein’s 3D structure, enables key advances in fundamental and applied research. Protein crystallization is a powerful technique to achieve this. Unlike Earth’s crystallization experiments, biomolecular crystallization in space in the absence of gravitational force is actively sought to improve crystal growth techniques. However, the effects of changing gravitational vectors on a protein solution reaching supersaturation remain largely unknown. Here, we have developed a low-cost crystallization cell within a CubeSat payload module to exploit the unique experimental conditions set aboard a sounding rocket. We designed a biaxial gimbal to house the crystallization experiments and take measurements on the protein solution in-flight with a spectrophotometry system. After flight, we used X-ray diffraction analysis to determine that flown protein has a structural rearrangement marked by loss of the protein’s water and sodium in a manner that differs from crystals grown on the ground. We finally show that our gimbal payload module design is a portable experimental setup to take laboratory research investigations into exploratory space flights.

The practice of serial X-ray crystallography (SX) depends on efficient, continuous delivery of hydrated protein crystals while minimizing background scattering. Of the two major types of sample delivery devices, fixed-target devices offer several advantages over widely adopted jet injectors, including: lower sample consumption, clog-free delivery, and the ability to control on-chip crystal density to improve hit rates. Here we present our development of versatile, inexpensive, and robust polymer microfluidic chips for routine and reliable room temperature serial measurements at both synchrotrons and X-ray free electron lasers (XFELs). Our design includes highly X-ray-transparent enclosing thin film layers tuned to minimize scatter background, adaptable sample flow layers tuned to match crystal size, and a large sample area compatible with both raster scanning and rotation based serial data collection. The optically transparent chips can be used both for in situ protein crystallization (to eliminate crystal handling) or crystal slurry loading, with prepared samples stable for weeks in a humidified environment and for several hours in ambient conditions. Serial oscillation crystallography, using a multi-crystal rotational data collection approach, at a microfocus synchrotron beamline (SSRL, beamline 12-1) was used to benchmark the performance of the chips. High-resolution structures (1.3-2.7 A) were collected from five different proteins - hen egg white lysozyme, thaumatin, bovine liver catalase, concanavalin-A (type VI), and SARS-CoV-2 nonstructural protein NSP5. Overall, our modular fabrication approach enables precise control over the cross-section of materials in the X-ray beam path and facilitates chip adaption to different sample and beamline requirements for user-friendly, straightforward diffraction measurements at room temperature.

Relaxases are metal-dependent nucleases that break and join DNA for the initiation and completion of conjugative bacterial gene transfer. Conjugation is the main process through which antibiotic resistance spreads among bacteria, with multidrug-resistant staphylococci and streptococci infections posing major threats to human health. The MOBV family of relaxases accounts for approximately 85% of all relaxases found in Staphylococcus aureus isolates. Here, we present six structures of the MOBV relaxase MobM from the promiscuous plasmid pMV158 in complex with several origin of transfer DNA fragments. A combined structural, biochemical, and computational approach reveals that MobM follows a previously uncharacterized histidine/metal-dependent DNA processing mechanism, which involves the formation of a covalent phosphoramidate histidine-DNA adduct for cell-to-cell transfer. We discuss how the chemical features of the high-energy phosphorus-nitrogen bond shape the dominant position of MOBV histidine relaxases among small promiscuous plasmids and their preference toward Gram-positive bacteria., The Institute for Research in Biomedicine Barcelona is the recipient of a Severo Ochoa Award of Excellence from the Spanish Ministry of Economy and Competitiveness (MINECO). The Molecular Biology Institute, Barcelona Spanish Research Council’s Structural Biology Unit is the recipient of a Maria de Maeztu Award of Excellence from MINECO. This work was supported by grants from MINECO (BFU2008-02372/ BMC, CSD-2006-23, BFU2011-22588, CSD-2008/00013, BIO2013-49148-C2-2-R, BFU2014-53550-P, BIO2015-69085-REDC, and BIO2015-64802), the Generalitat de Catalunya (2014-SGR134 and 2014-SGR1530), and the European Commission [project no. 260644, ERC_SimDNA, and the H2020 program (MuG and BioExcel Projects)]. R.P. and H.G. received a La Caixa/Institute for Research in Biomedicine Barcelona International PhD and Juan de La Cierva fellowship, respectively. M.O. is a Catalan Institution for Research and Advanced Studies Academia researcher.

Fungalysins are secreted fungal peptidases with the ability to degrade the extracellular matrix proteins elastin and collagen and are thought to act as virulence factors in diseases caused by fungi. Fungalysins constitute a unique family among zinc-dependent peptidases that bears low sequence similarity to known bacterial peptidases of the thermolysin family. The crystal structure of the archetype of the fungalysin family,Aspergillus fumigatusmetalloprotease (AfuMep), has been obtained for the first time. The 1.8 Å resolution structure of AfuMep corresponds to that of an autoproteolyzed proenzyme with separate polypeptide chains corresponding to the N-terminal prodomain in a binary complex with the C-terminal zinc-bound catalytic domain. The prodomain consists of a tandem of cystatin-like folds whose C-terminal end is buried into the active-site cleft of the catalytic domain. The catalytic domain harbouring the key catalytic zinc ion and its ligands, two histidines and one glutamic acid, undergoes a conspicuous rearrangement of its N-terminal end during maturation. One key positively charged amino-acid residue and the C-terminal disulfide bridge appear to contribute to its structural–functional properties. Thus, structural, biophysical and biochemical analysis were combined to provide a deeper comprehension of the underlying properties ofA. fumigatusfungalysin, serving as a framework for the as yet poorly known metallopeptidases from pathogenic fungi.

The conformational variation of three different proteins as a function of dose is examined at 278 and 100 K., Protein crystallography data collection at synchrotrons is routinely carried out at cryogenic temperatures to mitigate radiation damage. Although damage still takes place at 100 K and below, the immobilization of free radicals increases the lifetime of the crystals by approximately 100-fold. Recent studies have shown that flash-cooling decreases the heterogeneity of the conformational ensemble and can hide important functional mechanisms from observation. These discoveries have motivated increasing numbers of experiments to be carried out at room temperature. However, the trade-offs between increased risk of radiation damage and increased observation of alternative conformations at room temperature relative to cryogenic temperature have not been examined. A considerable amount of effort has previously been spent studying radiation damage at cryo-temperatures, but the relevance of these studies to room temperature diffraction is not well understood. Here, the effects of radiation damage on the conformational landscapes of three different proteins (T. danielli thaumatin, hen egg-white lysozyme and human cyclo­philin A) at room (278 K) and cryogenic (100 K) temperatures are investigated. Increasingly damaged datasets were collected at each temperature, up to a maximum dose of the order of 107 Gy at 100 K and 105 Gy at 278 K. Although it was not possible to discern a clear trend between damage and multiple conformations at either temperature, it was observed that disorder, monitored by B-factor-dependent crystallographic order parameters, increased with higher absorbed dose for the three proteins at 100 K. At 278 K, however, the total increase in this disorder was only statistically significant for thaumatin. A correlation between specific radiation damage affecting side chains and the amount of disorder was not observed. This analysis suggests that elevated conformational heterogeneity in crystal structures at room temperature is observed despite radiation damage, and not as a result thereof.

The human eosinophil cationic protein (ECP), also known as RNase 3, is an eosinophil secretion protein that is involved in innate immunity and displays antipathogen and proinflammatory activities. ECP has a high binding affinity for heterosaccharides, such as bacterial lipopolysaccharides and heparan sulfate found in the glycocalix of eukaryotic cells. We have crystallized ECP in complex with sulfate anions in a new monoclinic crystal form. In this form, the active site groove is exposed, providing an alternative model for ligand binding studies. By exploring the protein–sulfate complex, we have defined the sulfate binding site architecture. Three main sites (S1–S3) are located in the protein active site; S1 and S2 overlap with the phosphate binding sites involved in RNase nucleotide recognition. A new site (S3) that is unique to ECP is one of the key anchoring points for sulfated ligands. Arg 1 and Arg 7 in S3, together with Arg 34 and Arg 36 in S1, form the main basic clusters that assist in the recognition of ligand anionic groups. The location of additional sulfate bound molecules, some of which contribute to the crystal packing, may mimic the binding to extended anionic polymers. In conclusion, the structural data define a binding pattern for the recognition of sulfated molecules that can modulate the role of ECP in innate immunity. The results reveal the structural basis for the high affinity of ECP for glycosaminoglycans and can assist in structure-based drug design of inhibitors of the protein cytotoxicity to host tissues during inflammation.

The dehydration of crystals of macromolecules has long been known to have the potential to increase their diffraction quality. A number of methods exist to change the relative humidity that surrounds crystals, but for reproducible results, with complete characterization of the changes induced, a precise humidity-control device coupled with an X-ray source is required. The first step in these experiments is to define the relative humidity in equilibrium with the mother liquor of the system under study; this can often be quite time-consuming. In order to reduce the time spent on this stage of the experiment, the equilibrium relative humidity for a range of concentrations of the most commonly used precipitants has been measured. The relationship between the precipitant solution and equilibrium relative humidity is explained by Raoult's law for the equilibrium vapour pressure of water above a solution. The results also have implications for the choice of cryoprotectant and solutions used to dehydrate crystals. For the most commonly used precipitants (10-30% PEG 2000-8000), the starting point will be a relative humidity of 99.5%.

The Structural Molecular Biology group at SSRL has upgraded its crystal mounting robot (SAM) to enable a sample pin exchange time of approximately 25 s during automated screening of samples., The Stanford Automated Mounter System, a system for mounting and dismounting cryo-cooled crystals, has been upgraded to increase the throughput of samples on the macromolecular crystallography beamlines at the Stanford Synchrotron Radiation Lightsource. This upgrade speeds up robot maneuvers, reduces the heating/drying cycles, pre-fetches samples and adds an air-knife to remove frost from the gripper arms. Sample pin exchange during automated crystal quality screening now takes about 25 s, five times faster than before this upgrade.

TrwC is a DNA strand transferase that catalyzes the initial and final stages of conjugative DNA transfer. We have solved the crystal structure of the N-terminal relaxase domain of TrwC in complex with a 27 base-long DNA oligonucleotide that contains both the recognition hairpin and the scissile phosphate. In addition, a series of ternary structures of protein-DNA complexes with different divalent cations at the active site have been solved. Systematic anomalous difference analysis allowed us to determine unambiguously the nature of the metal bound. Zn2+, Ni2+ and Cu2+ were found to bind the histidine-triad metal binding site. Comparison of the structures of the different complexes suggests two pathways for the DNA to exit the active pocket. They are probably used at different steps of the conjugative DNA-processing reaction. The structural information allows us to propose (i) an enzyme mechanism where the scissile phosphate is polarized by the metal ion facilitating the nucleophilic attack of the catalytic tyrosine, and (ii) a probable sequence of events during conjugative DNA processing that explains the biological function of the relaxase. © 2006 Elsevier Ltd. All rights reserved., This study was supported by the Ministerio de Educación y Ciencia of Spain (grants BIO2002-03964, GEN2003-20642 and BFU2005-06758/BMC to M.C.; grant BMC2002-00379 to F.C.) and by the Generalitat de Catalunya (grant 2001SGR-346 to M.C.)

In this work, samarium(III) complexes with small peptides have been studied by potentiometric measurements. Experiments were performed in aqueous solution at 37.0 °C and 0.15 M NaClO 4 , resembling physiological medium. Low stability Sm(III)–peptide complexes were detected. Complexes with 1:1 ligand to metal molar ratio are predominant in the studied conditions. For Gly–Gly, the smallest dipeptide, [Sm(HL) 2 ] 3+ was also detected. For pH values greater than 6, hydrolysis to [Sm(OH)] 2+ and Sm(OH) 3 becomes the main process. One of these complexes was isolated and characterized in the solid state. X-ray structure of [Sm 2 (Gly–Val) 4 (H 2 O) 8 ](ClO 4 ) 6 ·2H 2 O is here reported. In this dimeric complex, two samarium atoms, with coordination number nine, are connected via four bridging carboxylate groups.

The structures of two new sulfate complexes are reported, namely di-mu-sulfato-kappa(3)O,O':O"-bis(aqua[2,4,6-tris(2-pyridyl)-1,3,5-triazine-kappa(3)N(1),N(2),N(6)]cadmium(II)) tetrahydrate, [Cd(2)(SO(4))(2)(C(16)H(12)N(6))(2)(H(2)O)(2)].4H(2)O, and di-mu-sulfato-kappa(2)O:O'-bis[(2,2':6',2"-terpyridine-kappa(3)N(1),N(1'),N(1"))zinc(II)] dihydrate, [Cd(2)(SO(4))(2)(C(15)H(11)N(3))(2)].2H(2)O, the former being the first report of a Cd(tpt) complex [tpt is 2,4,6-tris(2-pyridyl)-1,3,5-triazine]. Both compounds crystallize in the space group P-1 and form centrosymmetric dimeric structures. In the cadmium complex, the metal center is heptacoordinated in the form of a pentagonal bipyramid, while in the zinc complex, the metal ion is in a fivefold environment, the coordination geometry being intermediate between square pyramidal and trigonal bipyramidal. Packing of the dimers leads to the formation of planar structures strongly linked by hydrogen bonding.

International audience; Controlled dehydration of macromolecular crystals can lead to significant improvements in crystalline order, which often manifests itself in higher diffraction quality. Devices that can accurately control the humidity surrounding crystals on a beamline have led to this technique being increasingly adopted as experiments become easier and more reproducible. However, these experiments are often carried out by trial and error, and in order to facilitate and streamline them four European synchrotrons have established a collaboration around the HC1b dehydration device. The MAX IV Laboratory, Diamond Light Source, BESSY II, and the EMBL Grenoble Outstation/ESRF have pooled information gathered from user experiments, and on the use of the device, to propose a set of guidelines for these experiments. Here, we present the status and automation of the installations, advice on how best to perform experiments using the device, and an analysis of successful experiments that begins to show some trends in the type of protocols required by some systems. The dehydration methods shown are applicable to any device that allows control of the relative humidity of the air surrounding a macromolecular crystal

The crystal structure of the title complex, fluorene-1,3,5-trinitrobenzene (1.5/2) (1.5C 13 H 10 .2C 6 H 3 N 3 O 6 ) has been determined at room temperature. The molecule crystallizes in a triclinic cell and in the P1 space group. One of the three fluorene molecules in the unit cell is located at a special position and adopts two different orientations that are related by an inversion center. Therefore, the asymmetric unit contains 1.5 fluorene molecules and two molecules of 1,3,5-trinitrobenzene. Acceptor and donor molecules are arranged in mixed stacks, one with 1:1 and the other with 2:1 trinitrobenzene:fluorene stoichiometries. This mixed arrangement and the composition of the asymmetric unit explains the global 4:3 stoichiometry. These two independent stacking directions are parallel to the c and a axes, respectively.

The title compound, C13H20O3, crystallizes as a racemic mixture in which the two enantiomeric forms of the mol­ecule are related by an inversion center. The crystal structure confirms the one proposed on the basis of spectroscopic data and provides the information required to assign the relative stereochemistry of the chiral centers of the mol­ecule. The crystal packing is directed by intermolecular hydrogen bonds and short intramolecular C—H⋯O contacts.

A systematic study of the sensitivity to radiation damage of crystals held at room temperature for a large set of model macromolecular structures is presented., The radiation damage rates to crystals of 15 model macromolecular structures were studied using an automated radiation sensitivity characterization procedure. The diffracted intensity variation with dose is described by a two-parameter model. This model includes a strong resolution-independent decay specific to room-temperature measurements along with a linear increase in overall Debye–Waller factors. An equivalent representation of sensitivity via a single parameter, normalized half-dose, is introduced. This parameter varies by an order of magnitude between the different structures studied. The data show a correlation of crystal radiation sensitivity with crystal solvent content but no dose-rate dependency was detected in the range 0.05–300 kGy s−1. The results of the crystal characterization are suitable for either optimal planning of room-temperature data collection or in situ crystallization plate screening experiments.

The crystal structure of the adduct, C21H21NO2, of tetra­methyl­purpurogallin with nitro­so­benzene is reported. The compound exhibits a [3.2.2] bicyclic system corresponding to two seven-membered rings and one six-membered ring in distorted chair, boat and twist–boat conformations, respectively. One intramolecular and two intermolecular hydrogen bonds direct the packing and stabilize the mol­ecule.

The increase in the number of large multi-component complexes and membrane protein crystal structures determined over the last few years can be ascribed to a number of factors such as better protein expression and purification systems, the emergence of high-throughput crystallization techniques and the advent of 3rd generation synchrotron sources. However, many systems tend to produce crystals that can be extremely heterogeneous in their diffraction properties. This prevents, in many cases, the collection of diffraction data of sufficient quality to yield useful biological or phase information. Techniques that can increase the diffraction quality of macromolecular crystals can therefore be essential in the successful conclusion of these challenging projects. No technique is universal but encouraging results have been recently achieved by carrying out the controlled dehydration of crystals of biological macromolecules. A new device that delivers a stream of air with a precisely controlled relative humidity to the complicated sample environment found at modern synchrotron beamlines has been conceived at the EMBL Grenoble and developed by the EMBL and the ESRF as part of the SPINE2 complexes project, a European Commission funded protein structure initiative. The device, the HC1b, has been available for three years at the ESRF macromolecular crystallography beamlines and many systems have benefitted from on-line controlled dehydration. Here we describe a standard dehydration experiment, highlight some successful cases and discuss the different possible uses of the device.

The title compound, C 11 H 16 O 6 , has been synthesized and isolated as the major product of the osmylation of (5S,6R)-5,6-diacetoxy-1-methyl-1,3-cyclohexadiene. The molecule crystallizes in the monoclinic space group P2 1 . The hexene ring exhibits a puckered distorted half-chair conformation, with all the chiral centres (C3, C4, C5 and C6) in the S configuration. One intramolecular and two intermolecular hydrogen bonds stabilize the molecule by the formation of infinite chains along b.

Five novel ReIV-MII bimetallic complexes of formula [ReCl4(mu-mal)M(dmphen)2].MeCN [M = Co (1), Fe (2) and Ni (3)], [ReCl4(mu-mal)Ni(dmphen)(MeCN)2(H2O)].(MeCN)0.5(H2O)0.5 (4), and [ReCl4(mu-mal)Mn(dmphen)(H2O)2].dmphen.MeCN.H2O (5) (mal = malonate dianion, dmphen = 2,9-dimethyl-1,10-phenanthroline) have been synthesized, and the structures of 1, 2, 4, and 5 determined by single-crystal X-ray diffraction. The structures of 1 and 2 consist of neutral [ReCl4(mu-mal)M(dmphen)2] dinuclear units where the metal ions are linked through a malonate ligand which adopts simultaneously the bidentate (at ReIV) and monodentate (at MII) coordination modes. The bridging carboxylate-malonate group in them exhibits the anti-syn conformation. The rhenium atom is six-coordinated with four chloro atoms and two carboxylate-oxygens from a bidentate malonate group in a distorted octahedral environment. The M atom is five-coordinated being surrounded by four nitrogen atoms of two bidentate dmphen ligands and one oxygen atom of the malonato ligand. There are also ReIV(mu-mal)NiII dinuclear units in 4 with the same type of bridge, but the nickel atom is six-coordinated with one bidentate dmphen, two molecules of acetonitrile and one water molecule as peripheral ligands. Compound 5 is a neutral chain compound with regular alternating rhenium(IV) and manganese(II) ions. The [ReCl4(mal)]2- units in each chain act as bismonodenate ligands through two carboxylate-oxygen atoms toward [Mn(dmphen)(H2O)2]2+ entities. Variable-temperature magnetic measurements of 1-5 in the temperature range 2.0-300 K show the occurrence of weak antiferromagnetic interactions which are rationalized on the basis of the structural knowledge and simple orbital considerations. Very noticeable is compound 5, a ferrimagnetic chain with regular alternating ReIV and MnII cations.

A reflexão sobre o sentido de vida remonta à Antiguidade, e vários trabalhos têm sido desenvolvidos sobre a sua relação com outros construtos, inclusive valores. Os valores possuem conteúdos universais, transculturais, porém não é o caso de sentidos de vida, que não têm aparecido como meta implicita a todas as culturas. De acordo com a literatura, a busca pelo sentido de vida influencia os valores que orientam os comportamentos humanos. Tendo em vista a influência exercida pelos valores na gestão das organizações, este estudo teve como objetivo identificar a diferença entre sentidos de vida de gestores brasileiros e portugueses. A pesquisa caracterizou-se como descritiva exploratória, tendo empregado método quantitativo com aporte qualitativo. Os resultados evidenciaram diferenças entre as duas amostras: os brasileiros mais orientados para a auto-realização e os portugueses para a solidariedade com os grupos sociais próximos. The subject of life meaning has been discussed since ancient times, and several works have been developed on its relation with other constructs, including values. Values contain universal and transcultural content but life meanings haven’t appeared, in the studies, as a goal to all cultures. According with the literature, the search for life meaning influences the values that guide human behaviors. Regarding the role that values play on the management of organizations, this study aimed to identify the difference between the life meanings of Brazilian and Portuguese managers. The research was exploratory descriptive and had used a quantitative method with a qualitative approach. The results highlighted the differences between life meanings of the two samples: the Brazilians being more guided by the self-achievement, and the Portuguese by the solidarity with the social groups that surround them.

Protein crystallography data collection at synchrotrons today is routinely carried out at cryogenic temperatures to mitigate radiation damage to the crystal. Although damage still takes place, at 100 K and below, the immobilization of free radicals increases the lifetime of the crystals by orders of magnitude. Increasingly, experiments are carried out at room temperature. The lack of adequate cryo-protectants, the induced lattice changes or internal disorders during the cooling process, and the convenience of collecting data directly from the crystallization plates, are some of the reasons. Moreover, recent studies have shown that flash-freezing affects the conformational ensemble of crystal structures [1], and can hide important functional mechanisms from observation [2]. While there has been a considerable amount of effort in studying radiation damage at cryo-temperatures, its effects at room temperature are still not well understood. We investigated the effects of data collection temperature on secondary local damage to the side chain and main chain from different proteins. Data were collected from crystals of thaumatin and lysozyme at 100 K and room temperature. To carefully control the total absorbed dose, full data sets at room temperature were assembled from a few diffraction images per crystal. Several data sets were collected at increasing levels of absorbed dose. Our analysis shows that while at cryogenic temperatures, radiation damage increases the conformational variability, _x0004_at room temperature it has the opposite effect_x0005_. We also observed that disulfide bonds appear to break up at a different relative rate at room temperature, perhaps because of a more active repair mechanism. Our analysis suggests that elevated conformational heterogeneity in crystal structures at room temperature is observed despite radiation damage, and not as a result thereof.

Tri­chloro­oxo­[1,3-prop­ane­diyl­bis­(di­phenyl­phosphine)-P,P′]rhen­ium(V), [Re­Cl3­O­(C27­H26P2)], crystallizes with four formula units per unit cell. The crystal structure consists of neutral complexes of [ReOCl3(dppp)] [dppp is 1,3-bis(diphenylphosphino)propane] packed by H⋯π-ring interactions. The Re atom is octahedrally coordinated to the oxo anion, three Cl atoms and two P atoms from the dppp ligand. The six-membered ring formed by the bidentate dppp ligand and the rhenium metal centre is in a chair conformation. The title compound is an intermediate in the synthesis of bis(dppp) complexes of rhenium.

The title compound, [Fe(C8H11ClO2)(CO)3], has been synthesized, isolated and characterized by single-crystal X-ray diffraction. The mol­ecule crystallizes in the orthorhombic space group P212121. The metal–ligand arrangement is typical of (1,3-diene)­tri­carbonyl­iron complexes.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior This is a research anchored in interpretative approach to the competence studies that set out to study the phenomenon of development competence of social entrepreneurs as Ways of Being (SANDBERG; DALL'ALBA, 2006; SANDBERG; PINNINGTON, 2009). Therefore, we analyze the trajectories of a group of four companies entrepreneurs who has managed publicly recognized results in the state of Alagoas, highlighting the experiences along the way, since the establishment of business to its consolidation. A central question guided the thesis: considering the experiences of a group of social entrepreneurs, what can you learn about the process of developing their competence that allowed achieve social impact and financial sustainability? The narrative analysis was defined as research proposal. The narrative interviews were the primary data building strategy, followed by document analysis. The data were interpreted built from the proposed thematic analysis narrative Riessman (2008). Was taken as an object of study, the experiences of 13 social business founders of the state of Alagoas, two technology-based and two health. As a result, the experiences of entrepreneurs pointed to the flow that the constituent aspects of competence were mobilized in the context and changed their actions in a process as ways of being social entrepreneurs. Five core elements revealed in narratives constructed by the owners partners in telling the story of the construction and consolidation of the business, and how to develop competence that led to the public recognition and self financial sustainability, they are: direct contact owners partners with problems of social reality; the material and human conditions created by them; the process of seeing themselves as social entrepreneurs; the sharing of meanings and competence development. From the point of view of theoretical implications, which the constituents of the narratives show is that while the technology-based companies and health services are very different, they revealed a very similar flow in the process as ways of being competent. The way these entrepreneurs told their stories and explained the development of individual and collective competence reflects, above all, the construction and consolidation of their identity as social entrepreneurs. From the point of view of the practical implications, the flow identified with the core elements can serve as benchmarks for start-ups and developing self analyze their own trajectory, identifying advances in building a social business identity, collectively, to strengthen the competence of the business. From a methodological point of view, there is the use of narrative research as a methodological proposal. This option proved to be rich and interesting to qualitatively understand the phenomenon of the development of social competence in business, allowing reveal processes underlying the materialization of competences. Trata-se de uma pesquisa ancorada na abordagem interpretativista dos estudos em competências que se propôs a estudar o fenômeno do desenvolvimento da competência de empreendedores sociais enquanto um processo de “vir a ser” (SANDBERG; DALL'ALBA, 2006; SANDBERG; PINNINGTON, 2009). Para tanto, analisam-se as trajetórias de um grupo de empreendedores de quatro empresas que vem conseguindo resultados reconhecidos publicamente no Estado de Alagoas, destacando as experiências vivenciadas no percurso, desde a constituição do negócio à sua consolidação. Uma questão central norteou a tese: considerando as experiências de um grupo de empreendedores sociais, o que se pode apreender sobre o processo de desenvolvimento de suas competências que permitiram alcançar impacto social e sustentabilidade financeira? A análise de narrativas foi definida como proposta de investigação. As entrevistas narrativas foram a principal estratégia de construção dos dados, seguida de análise documental. Os dados construídos foram interpretados a partir da proposta de análise temática de narrativa de Riessman (2008). Tomaram-se como objeto de estudo as experiências de 13 sócios fundadores de negócios sociais do estado de Alagoas, dois de base tecnológica e dois da área da saúde. Como resultado, as experiências dos empreendedores apontaram o fluxo com que os aspectos constituintes da competência foram mobilizados no contexto e ressignificaram as ações, num processo de virem a ser empreendedores sociais. Cinco elementos centrais se revelaram nas narrativas construídas pelos sócios proprietários, ao contar a história da construção e consolidação do negócio, e como desenvolveram competências que os levaram ao reconhecimento público e à autossustentabilidade financeira, são eles: o contato direto dos sócios-proprietários com os problemas da realidade social; as condições materiais e humanas criadas por eles; o processo de se verem como empreendedores sociais; o compartilhamento de significados e o desenvolvimento de competências. Do ponto de vista das implicações teóricas, o que esses elementos constitutivos das narrativas mostraram é que, embora as empresas de base tecnológica e de serviços de saúde sejam muito diferentes, elas revelaram um fluxo muito semelhante no processo de virem a ser competentes. A forma como esses empreendedores contaram suas histórias e explicaram o desenvolvimento da competência individual e coletiva reflete, acima de tudo, a construção e consolidação de sua identidade como empreendedores sociais. Do ponto de vista das implicações práticas, o fluxo identificado com os elementos centrais pode servir de parâmetros de referência para as empresas nascentes e em desenvolvimento autoanalisarem sua própria trajetória, identificando os avanços na construção de uma identidade de negócio social, coletivamente, que fortaleça a competência do negócio. Do ponto de vista metodológico, destaca-se a utilização da pesquisa narrativa como proposta metodológica. Tal opção mostrou-se rica e interessante para compreender qualitativamente o fenômeno do desenvolvimento da competência em negócio social, permitindo revelar processos subjacentes à materialização das competências.