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The Protein Data Bank in Europe (PDBe; pdbe.org) is a partner in the Worldwide PDB organization (wwPDB; wwpdb.org) and as such actively involved in managing the single global archive of biomacromolecular structure data, the PDB. In addition, PDBe develops tools, services and resources to make structure-related data more accessible to the biomedical community. Here we describe recently developed, extended or improved services, including an animated structure-presentation widget (PDBportfolio), a widget to graphically display the coverage of any UniProt sequence in the PDB (UniPDB), chemistry- and taxonomy-based PDB-archive browsers (PDBeXplore), and a tool for interactive visualization of NMR structures, corresponding experimental data as well as validation and analysis results (Vivaldi).

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The Protein Data Bank in Europe (PDBe) (http://www.ebi.ac.uk/pdbe/) is actively working with its Worldwide Protein Data Bank partners to enhance the quality and consistency of the international archive of bio-macromolecular structure data, the Protein Data Bank (PDB). PDBe also works closely with its collaborators at the European Bioinformatics Institute and the scientific community around the world to enhance its databases and services by adding curated and actively maintained derived data to the existing structural data in the PDB. We have developed a new database infrastructure based on the remediated PDB archive data and a specially designed database for storing information on interactions between proteins and bound molecules. The group has developed new services that allow users to carry out simple textual queries or more complex 3D structure-based queries. The newly designed 'PDBeView Atlas pages' provide an overview of an individual PDB entry in a user-friendly layout and serve as a starting point to further explore the information available in the PDBe database. PDBe's active involvement with the X-ray crystallography, Nuclear Magnetic Resonance spectroscopy and cryo-Electron Microscopy communities have resulted in improved tools for structure deposition and analysis.

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Staphylococcus aureus can cause disease through the production of toxins. Toxin production is autoinduced by the protein RNAIII-activating protein (RAP) and by the autoinducing peptide (AIP), and is inhibited by RNAIII-inhibiting peptide (RIP) and by inhibitory AIPs. RAP has been shown to be a useful vaccine target site, and RIP and inhibitory AIPs as therapeutic molecules to prevent and suppress S. aureus infections. Development of therapeutic strategies based on these molecules has been hindered by a lack of knowledge of the molecular mechanisms by which they activate or inhibit virulence. Here, we show that RAP specifically induces the phosphorylation of a novel 21-kDa protein, whereas RIP inhibits its phosphorylation. This protein was termed target of RAP (TRAP). The synthesis of the virulence regulatory molecule, RNAIII, is not activated by RAP in the trap mutant strain, suggesting that RAP activates RNAIII synthesis via TRAP. Phosphoamino acid analysis shows that TRAP is histidine-phosphorylated, suggesting that TRAP may be a sensor of RAP. AIPs up-regulate the synthesis of RNAIII also in trap mutant strains, suggesting that TRAP and AIPs activate RNAIII synthesis via distinct signal transduction pathways. Furthermore, TRAP phosphorylation is down-regulated in the presence of AIP, suggesting that a network of signal transduction pathways regulate S. aureus pathogenesis.

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Crystal structures are presented for the A197C mutant of Escherichia coli phosphate binding protein (PBP) and the same mutant labeled at Cys197 with N-[2-(1-maleimidyl)ethyl]-7-(diethylamino)coumarin-3-carboxamide (MDCC). Both proteins are complexed with inorganic phosphate. The latter molecule, MDCC-PBP, exhibits a large increase in fluorescence on binding inorganic phosphate. The resulting high-fluorescence state of the coumarin and the ability of this coumarin to monitor the conformational changes associated with inorganic phosphate binding are interpreted in terms of the specific interactions of MDCC with the protein. The structure helps to explain why this particular label gives a high-fluorescence state on binding inorganic phosphate, while several other related labels do not, and hence aids our general understanding of environmentally sensitive fluorescence probes on proteins.

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The small molecular weight GTP-binding protein Rac (1 or 2) is an obligatory participant in the activation of the superoxide-generating NADPH oxidase. Active NADPH oxidase can be reconstituted in a cell-free system, consisting of phagocyte-derived membranes, containing cytochrome b559, and the recombinant cytosolic proteins p47-phox, p67-phox, and Rac, supplemented with an anionic amphiphile as an activator. The cell-free system was used before for the analysis of structural requirements of individual components participating in the assembly of NADPH oxidase. In earlier work, we mapped four previously unidentified domains in Rac1, encompassing residues 73-81 (a), 103-107 (b), 123-133 (c), and 163-169 (d), as important for cell-free NADPH oxidase activation. The domains were defined by assessing the activation inhibitory effect of a series of overlapping peptides, spanning the entire length of Rac1 [Joseph, G., and Pick, E. (1995) J. Biol. Chem. 270, 29079-29082]. We now used the construction of Rac1/H-Ras chimeras, domain deletion, and point mutations, to ascertain the functional relevance of three domains (b, c, and d) predicted by "peptide walking" and to determine the importance of specific residues within these domains. This methodology firmly establishes the involvement of domains b and d in the activation of NADPH oxidase by Rac1 and identifies H103 and K166, respectively, as residues critical for the effector function of these two domains. The functional significance of domain c (insert region) could not be confirmed, as shown by the minor effect of deleting this domain on NADPH oxidase activation. Analysis of the three-dimensional structure of Rac1 reveals that residues H103 and K166 are exposed on the surface of the molecule. Modeling of the activity-impairing point mutations suggests that the effect on the ability to activate NADPH oxidase depends on the side chains of the mutated amino acids and not on changes in the global structure of the protein. In conclusion, we demonstrate the existence of two novel effector sites in Rac1, necessary for supporting NADPH oxidase activation, supplementing the canonical N-terminal effector region.

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Activation of the respiratory burst oxidase involves the assembly of the membrane-associated flavocytochrome b558 with the cytosolic components p47(phox), p67(phox), and the small GTPase Rac. Herein, the interaction between Rac and p67(phox) is explored using functional and physical methods. Mutually facilitated binding (EC50) of Rac1 and p67(phox) within the NADPH oxidase complex was demonstrated using steady state kinetic methods measuring NADPH-dependent superoxide generation. Direct binding of Rac1 and Rac2 to p67(phox) was shown using a fluorescent analog of GTP (methylanthraniloyl guanosine-5'-[beta,gamma-imido]triphosphate) bound to Rac as a reporter group. An increase in the methylanthraniloyl fluorescence was seen with added p67(phox) but not p47(phox), and the emission maximum shifted from 445 to 440 nm. Rac1 and Rac2 bound to p67(phox) with a 1:1 stoichiometry and with Kd values of 120 and 60 nM, respectively. Mutational studies (Freeman, J., Kreck, M., Uhlinger, D. J., and Lambeth, J. D. (1994) Biochemistry 33, 13431-13435; Freeman, J. L., Abo, A., and Lambeth, J. D. (1996) J. Biol. Chem. 271, 19794-19801) previously identified two regions in Rac1 that are important for activity: the "effector region" (residues 26-45) and the "insert region" (residues 124-135). Proteins mutated in the effector region (Rac1(N26H), Rac1(I33N), and Rac1(D38N)) showed a marked increase in both the Kd and the EC50, indicating that mutations in this region affect activity by inhibiting Rac binding to p67(phox). Insert region mutations (Rac1(K132E) and L134R), while showing markedly elevated EC50 values, bound with normal affinity to p67(phox). The structure of Rac1 determined by x-ray crystallography reveals that the effector region and the insert region are located in defined sectors on the surface of Rac1. A model is discussed in which the Rac1 effector region binds to p67(phox), the C terminus binds to the membrane, and the insert region interacts with a different protein component, possibly cytochrome b558.

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The crystal structure of human rac1, a member of the rho family of small G-proteins, complexed with the non-hydrolysable GTP analogue, guanosine-5'-(beta gamma-imino)triphosphate (GMPPNP), has been determined by X-ray analysis at a resolution of 1.38 A. Comparison with the structure of H-ras indicates that rac1 has an extra alpha-helical domain that is characteristic of the rho G proteins, and may be involved in the signalling pathway of this family.

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A preliminary X-ray crystallographic study of a novel zinc-binding protein from maize is presented. Native and several heavy-atom derivative sets of data have been collected on synchrotron sources, to a resolution of 2.1 A. The space group was found to be orthorhombic, P2(1)2(1)2(1), with unit-cell dimensions of a = 92.64, b = 129.45 and c = 196.31 A.

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The importance of amino acid side-chains in helix stability has been investigated by making a series of mutations at the N-caps, C-caps and internal positions of the solvent-exposed faces of the two alpha-helices of barnase. There is a strong positional and context dependence of the effect of a particular amino acid on stability. Correlations have been found that provide insight into the physical basis of helix stabilization. The relative effects of Ala and Gly (or Ser) may be rationalized on the basis of solvent-accessible surface areas: burial of hydrophobic surface stabilizes the protein as does exposure to solvent of unpaired hydrogen bond donors or acceptors in the protein. There is a good correlation between the relative stabilizing effects of Ala and Gly at internal positions with the total change in solvent-accessible hydrophobic surface area of the folded protein on mutation of Ala----Gly. The relationship may be extended to the N and C-caps by including an extra term in hydrophilic surface area for the solvent exposure of the non-intramolecularly hydrogen-bonded main-chain CO, NH or protein side-chain hydrogen bonding groups. The requirement for solvent exposure of the C-cap main-chain CO groups may account for the strong preference for residues having positive phi and psi angles at this position, since this alpha L-conformation results in the largest solvent exposure of the C-terminal CO groups. Glycine in an alpha L-conformation results in the greatest exposure of these CO groups. Further, the side-chains of His, Asn, Arg and Lys may, with positive phi and psi-angles, form a hydrogen bond with the backbone CO of residue in position C -3 (residues are numbered relative to the C-cap). The preferences at the C-cap are Gly much greater than His greater than Asn greater than Arg greater than Lys greater than Ala approximately Ser approximately greater than Asp. The preferences at the N-cap are determined by hydrogen bonding of side-chains or solvent to the exposed backbone NH groups and are: Thr approximately Asp approximately Ser greater than Gly approximately Asn greater than Gln approximately Glu approximately His greater than Ala greater than Val much greater than Pro. These general trends may be obscured when mutation allows another side-chain to become a surrogate cap.(ABSTRACT TRUNCATED AT 400 WORDS)

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1. Twenty seven consecutive cases of preparalytic infantile paralysis (36.4% of the total admissions) treated with non-specific protein (intramuscular sterile milk), intravenous 50% sucrose and dehydration (restricted intake) are herein reported. There was no paralysis nor mortality in this group. One case developed weakness, which subsequently disappeared entirely before hospital discharge. During a simultaneous period, 47 cases (63.6%) were admitted with either weakness or paralysis. 2. The early administration of this therapy is advocated. 3. The therapy was used in cases presenting muscular weakness and paralysis upon hospital admission with apparent arrest of the process sooner than is usually expected. A rapid recovery was striking in many instances. This was particularly true in the group admitted with weakness only. 73% of these recovered completely and the remaining 27% were improved. In the paralytic group ganglion cell destruction had often completed before hospital admission. In these cases the results would be disappointing with any therapy. 4. Of the 47 cases admitted in the stage of weakness or paralysis, including the bulbar cases, twelve (25.5%) recovered completely, 17 (36.1%) definitely improved, 16 (34%) were unimproved and 2 (4.2%) died. In the entire group (74 cases) there was a mortality of 2.7%, complete recovery in 52.7%, improvement 22.9% and no improvement in 21.6%. 5. Aside from poliomyelitis, we have used the therapy in primary and secondary encephalitis with gratifying results in most cases, which, however, were few in number. 6. Further study on a larger scale would be advantageous in evaluating this therapy, both in poliomyelitis and encephalitis.

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Structural modelling techniques using energy minimization and molecular dynamics have been employed to generate kinked models for the solution structure of two DNA tridecamer sequences containing inserted adenosines: d(CGCAGAATTCGCG)2 and d(CGCAGAGCTCGCG)2. These models are consistent with NMR studies of these sequences in solution. The overall shapes of the two models are similar, consisting of three B-DNA sections: two outer segments on the same side of the central portion, with the additional adenosines acting as wedges to kink the structure. An alternative scheme for the hydrogen bond pairing at the kink site is suggested as a way for the additional adenosines to be stabilized in the duplex.

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Fifty-four primiparous women were administered the Zung Self-rating Depression Scale and the Objective Social Perception Inventory during the last trimester of pregnancy. Four to 8 weeks postpartum, they again responded to the SRDS. A poor relationship with the husband, as rated during pregnancy, was significantly associated with depression during pregnancy and was also predictive of depression after childbirth. No parallel association between relationship with the mother and depression pre- or postpartum was noted.

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