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The X-ray crystal structure of chitin oligosaccharide deacetylase from Vibrio parahaemolyticus ( Vp -COD) was determined at an 1.35 Å resolution. The amino acid sequence and structure of Vp -COD show that the enzyme comprises one polysaccharide deacetylase domain (PDD) and two carbohydrate-binding domains (CBDs). On the basis of a chitin-binding assay with Vp -COD and its CBDs-deleted mutant, it was confirmed that CBDs can adhere to chitin. The catalytic activity of the CBDs-deleted mutant was only mildly depressed compared with that of Vp -COD, indicating that CBDs are unlikely to affect the configuration of the active center residues in active site of PDD. [ABSTRACT FROM AUTHOR]

Influenza virus RNA-dependent RNA polymerase is a multi-functional heterotrimer, which uses a ‘cap-snatching’ mechanism to produce viral mRNA. Host cell mRNA is cleaved to yield a cap-bearing oligonucleotide, which can be extended using viral genomic RNA as a template. The cap-binding and endonuclease activities are only activated once viral genomic RNA is bound. This requires signalling from the RNA-binding PB1 subunit to the cap-binding PB2 subunit, and the interface between these two subunits is essential for the polymerase activity. We have defined this interaction surface by protein crystallography and tested the effects of mutating contact residues on the function of the holo-enzyme. This novel interface is surprisingly small, yet, it has a crucial function in regulating the 250 kDa polymerase complex and is completely conserved among avian and human influenza viruses. [ABSTRACT FROM AUTHOR]

Objective and background: Interferon γ-inducible protein (IP)-10 and epithelial neutrophil-activating peptide (ENA)-78 belong to the CXC chemokine family and are important factors in inflammatory lung diseases. In sarcoidosis, the potential role of IP-10 to regulate the migration and activation of T-cells towards sites of sarcoid activity has been suggested. Methods: In this study, the concentrations of IP-10 and ENA-78 in the serum and BAL fluid of patients with different stages of active pulmonary sarcoidosis ( n = 41) and healthy subjects ( n = 12) were measured by enzyme-linked immunosorbent assay to evaluate the contribution of these CXC chemokines to this disease. Results: Serum and BAL fluid concentrations of IP-10 and BAL fluid levels of ENA-78 in patients with sarcoidosis were significantly higher than those in control subjects. The serum levels of IP-10 were significantly increased only in patients with stages I and II sarcoidosis, while BAL fluid levels of ENA-78 were increased only in stage III sarcoidosis. In addition, serum concentrations of IP-10 were elevated in patients with extrapulmonary lesions compared with those without such lesions. In patients with sarcoidosis, IP-10 concentrations in BAL fluid correlated with lymphocyte proportions in BAL fluid. Conclusion: IP-10 may play an important role in regulating lymphocytes into the lung and that ENA-78 may be associated with lung parenchymal disease in pulmonary sarcoidosis. [ABSTRACT FROM AUTHOR]

Two male industrial painters were admitted to hospital with dry cough and dyspnoea on exertion following a tank coating operation using a high-temperature spray paint consisting of a nickel-chromium alloy. Both patients showed hypoxaemia, peripheral leukocytosis, high levels of serum cytokines and bilateral ground-glass opacities on a chest CT scan. They were diagnosed with interstitial pneumonia caused by inhalation of nickel and chrome fumes and successfully treated with corticosteroid. These are rare cases of interstitial pneumonia associated with nickel/chromium inhalation. [ABSTRACT FROM AUTHOR]

The Streptomyces butyrolactone autoregulator receptor protein (BarA) is a DNA-binding protein that regulates the biosynthesis of the antibiotic virginiamycin. In this study, BarA from S. virginiae was overexpressed in Escherichia coli, purified and crystallized. Crystals of purified protein have been grown that diffracted to beyond 3.0 Å resolution at 100 K using synchrotron radiation. The protein crystals belonged to the hexagonal space group P6522, with unit-cell parameters a = b = 128.0, c = 286.2 Å. With four molecules per asymmetric unit, the crystal volume per unit protein mass ( VM) was 3.2 Å3 Da−1 and the solvent content was 62%. [ABSTRACT FROM AUTHOR]