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Background: Cryopyrin-associated periodic syndrome (CAPS) is a group of rare, heterogeneous autoinflammatory disease characterized by interleukin (IL)-1β-mediated systemic inflammation and clinical symptoms involving skin, joints, central nervous system, and eyes. It encompasses a spectrum of three clinically overlapping autoinflammatory syndromes including familial cold autoinflammatory syndrome, Muckle-Wells syndrome (MWS), and neonatal-onset multisystem inflammatory disease. CAPS is associated with gain-of-function missense mutations in NOD-like receptor family pyrin domain-containing protein 3 (NLRP3), the gene encoding NLRP3. Moreover, most mutations leading to MWS occurred in exon 3 of NLRP3 gene. Here, we reported a novel mutation occurred in exon 1 of NLRP3 gene in an MWS patient and attempted to explore the pathogenic mechanism. Methods: Genetic sequence analysis of NLRP3 was performed in an MWS patient who presented with periodic fever, arthralgia, and multiform skin lesions. NLRP3 was also analyzed in this patient's parents and 50 healthy individuals. Clinical examinations including X-ray examination, skin biopsy, bone marrow aspiration smear, and blood test of C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), serum levels of IL-1β, immunoglobulin E (IgE), antineutrophil cytoplasmic antibodies, antinuclear antibodies, and extractable nuclear antigen were also analyzed. The protein structure of mutant NLRP3 inflammasome was calculated by SWISS-MODEL software. Proteins of wild type and mutant components of NLRP3 inflammasome were expressed and purified, and the interaction abilities between these proteins were tested by surface plasmon resonance (SPR) assay. Results: X-ray examination showed no abnormality in the patient's knees. Laboratory tests indicated an elevation of CRP (233.24 mg/L) and ESR (67 mm/h) when the patient had fever. Serum IL-1β increased to 24.37 pg/ml, and serum IgE was higher than 2500.00 IU/ml. Other blood tests were normal. Bone marrow aspiration smear was normal. A novel point mutation c.92A>T in exon 1 of NLRP3 gene was identified, which caused a p.D31V mutation in pyrin domain (PYD) of NLRP3. SPR assay showed that this point mutation may strengthen the interaction between the PYD of NLRP3 and the PYD of the apoptosis-associated speck-like protein. The mutation c.92A>T in exon 1 of the NLRP3 gene was not found in the patient's parents and 50 healthy individuals. Conclusions: The mutation c.92A>T in exon 1 of the NLRP3 gene is a novel mutation associated with MWS. The p.D31V mutation might promote the activation of NLRP3 inflammasome and induce MWS in this patient.

The open reading frame SCO4226 of Streptomyces coelicolor A3(2) encodes an 82-residue hypothetical protein. Biochemical assays revealed that each SCO4226 dimer binds four nickel ions. To decipher the molecular function, we solved the crystal structures of SCO4226 in both apo- and nickel-bound (Ni-SCO4226) forms at 1.30 and 2.04 Å resolution, respectively. Each subunit of SCO4226 dimer adopts a canonical ferredoxin-like fold with five β-strands flanked by two α-helices. In the structure of Ni-SCO4226, four nickel ions are coordinated at the surface of the dimer. Further biochemical assays suggested that the binding of Ni2+ triggers the self-aggregation of SCO4226 in vitro. In addition, RT-qPCR assays demonstrated that the expression of SCO4226 gene in S. coelicolor is specifically up-regulated by the addition of Ni2+, but not other divalent ions such as Cu2+, Mn2+ or Co2+. All these results suggested that SCO4226 acts as a nickel binding protein, probably required for nickel sequestration and/or detoxification.

Objective To study the correlation of the expression of long non-coding RNA zinc finger antisense 1 (lncRNA ZFAS1) and hsa-miR-372-3p in lung cancer tissues with the malignant characteristics and prognosis of patients. Methods Eighty-two lung cancer patients hospitalized in Shijiazhuang People's Hospital from March 2015 to October 2016 were selected. The expression of ZFAS1 and miR-372-3p in lung cancer tissues and in adjacent tissues, the potential correlation of the level of ZFAS1 and miR-372-3p with malignant characteristics of patients were analyzed; Pearson method was used to analyze the relationship between ZFAS1 and miR-372-3p in lung cancer tissues; Kaplan-Meier was used to analyze the correlation of the expression of ZFAS1 and miR-372-3p with the prognosis of patients; COX regression was used to analyze the risk factors for poor prognosis of lung cancer patients. Results Compared with the situation of adjacent tissues, the expression of ZFAS1 and miR-372-3p in tumor tissue was significantly higher (P＜0.05). The expression of ZFAS1 and miR-372-3p in tumor tissue was related to TNM staging, lung membrane infiltration, whether lymph node metastasis occurred, and the degree of tumor differentiation (P＜0.05). The expression of ZFAS1 and miR-372-3p content in lung cancer tissues was significantly and positively correlated (r=0.477, P＜0.001). The 5-year survival rate of patients in the ZFAS1 and miR-372-3p high expression group was significantly lower than the low expression group (P＜0.05). TNM staging, lymph node metastasis, ZFAS1, and miR-372-3p were independent risk factors for poor prognosis in patients with lung cancer(P＜0.05). Conclusions ZFAS1 and miR-372-3p are highly expressed in lung cancer tissues and the expression level is related to the malignant characteristics and prognosis of lung cancer patients, so it may be regarded as an independent risk factor to predict poor prognosis of lung cancer patients.

GAK (cyclin G-associated kinase) is a key regulator of clathrincoated vesicle trafficking and plays a central role during development. Additionally, due to the unusually high plasticity of its catalytic domain, it is a frequent 'off-target' of clinical kinase inhibitors associated with respiratory side effects of these drugs. In the present paper, we determined the crystal structure of the GAK catalytic domain alone and in complex with specific singlechain antibodies (nanobodies). GAK is constitutively active and weakly associates in solution. The GAK apo structure revealed a dimeric inactive state of the catalytic domain mediated by an unusual activation segment interaction. Co-crystallization with the nanobody NbGAK_4 trapped GAK in a dimeric arrangement similar to the one observed in the apo structure, whereas NbGAK_1 captured the activation segment of monomericGAKin a well-ordered conformation, representing features of the active kinase. The presented structural and biochemical data provide insight into the domain plasticity of GAK and demonstrate the utility of nanobodies to gain insight into conformational changes of dynamic molecules. In addition, we present structural data on the binding mode of ATP mimetic inhibitors and enzyme kinetic data, which will support rational inhibitor design of inhibitors to reduce the off-target effect on GAK. [ABSTRACT FROM AUTHOR]

The 19ID undulator beamline of the Structure Biology Center has been designed and built to take full advantage of the high flux, brilliance and quality of X-ray beams delivered by the Advanced Photon Source. The beamline optics are capable of delivering monochromatic X-rays with photon energies from 3.5 to 20 keV (3.5–0.6 Å wavelength) with fluxes up to 8–18 × 1012 photons s−1 (depending on photon energy) onto cryogenically cooled crystal samples. The size of the beam (full width at half-maximum) at the sample position can be varied from 2.2 mm × 1.0 mm (horizontal × vertical, unfocused) to 0.083 mm × 0.020 mm in its fully focused configuration. Specimen-to-detector distances of between 100 mm and 1500 mm can be used. The high flexibility, inherent in the design of the optics, coupled with a κ-geometry goniometer and beamline control software allows optimal strategies to be adopted in protein crystallographic experiments, thus maximizing the chances of their success. A large-area mosaic 3 × 3 CCD detector allows high-quality diffraction data to be measured rapidly to the crystal diffraction limits. The beamline layout and the X-ray optical and endstation components are described in detail, and the results of representative crystallographic experiments are presented. [ABSTRACT FROM AUTHOR]

Genetic recombination in bacteriophage λ relies on DNA end processing by Exo to expose 3'-tailed strands for annealing and exchange by β protein. Phage λ encodes an additional recombinase, Orf, which participates in the early stages of recombination by supplying a function equivalent to the Escherichia coli RecFOR complex. These host enzymes assist loading of the RecA strand exchange protein onto ssDNA coated with ssDNA-binding protein. In this study, we purified the Orf protein, analyzed its biochemical properties, and determined its crystal structure at 2.5 Å. The homodimeric Orf protein is arranged as a toroid with a shallow U-shaped cleft, lined with basic residues, running perpendicular to the central cavity. Orf binds DNA, favoring single-stranded over duplex and with no obvious preference for gapped, 3'-tailed, or 5'-tailed substrates. An interaction between Orf and ssDNA- binding protein was indicated by far Western analysis. The functional similarities between Orf and RecFOR are discussed in relation to the early steps of recombinational exchange and the interplay between phage and bacterial recombinases. [ABSTRACT FROM AUTHOR]

Presents the crystal structure of an Enterococcus faecalis protein SlyA transcriptional regulator. Multiple sequence alignment; Phylogenetic relationships; Interaction with DNA.

Focuses on a study which analyzed the structure of a LuxR-type protein of Vibrio fischeri. Information on bacterial communication; Comparison between LuxR and TraR of Agrobacterium tumefaciens; Discussion of the DNA-binding domain of TraR protein.

Attempts to provide a basis for the evaluation of inosine monophosphate dehydrogenase (IMPDH) inhibitors as antimicrobial agents. Expression and characterization of IMPDH from the pathogenic bacterium Streptococcus pyrogenes; Lack of sensitivity to mycophenolic acid; Role of various active site regions in catalysis.

A letter to the editor is presented about the significance of reductive methylation to achieve improved protein crystallization.

A correction to the article "Structure of a bacterial quorum-sensing transcription factor complexed with pheromone and DNA" that was published in the 2002 issue is presented.

Gastric cancer (GC) is one of the most common carcinoma and the second leading cause of cancer-related deaths worldwide. Helicobacter pylori (H. pylori) infection causes a series of precancerous lesions like gastritis, atrophy, intestinal metaplasia and dysplasia, and is the strongest known risk factor for GC, as supported by epidemiological, preclinical and clinical studies. However, the mechanism of H. pylori developing gastric carcinoma has not been well defined. Among infected individuals, approximately 10% develop severe gastric lesions such as peptic ulcer disease, 1%-3% progresses to GC. The outcomes of H. pylori infection are determined by bacterial virulence, genetic polymorphism of hosts as well as environmental factors. It is important to gain further understanding of the pathogenesis of H. pylori infection for developing more effective treatments for this common but deadly malignancy. The recent findings on the bacterial virulence factors, effects of H. pylori on epithelial cells, genetic polymorphism of both the bacterium and its host, and the environmental factors for GC are discussed with focus on the role of H. pylori in gastric carcinogenesis in this review.