Many bacteria in the environment have adapted to the presence of toxic heavy metals. Over the last 30 years, this heavy metal tolerance was the subject of extensive research. The bacterium Cupriavidus metallidurans strain CH34, originally isolated by us in 1976 from a metal processing factory, is considered a major model organism in this field because it withstands milli-molar range concentrations of over 20 different heavy metal ions. This tolerance is mostly achieved by rapid ion efflux but also by metal-complexation and -reduction. We present here the full genome sequence of strain CH34 and the manual annotation of all its genes. The genome of C. metallidurans CH34 is composed of two large circular chromosomes CHR1 and CHR2 of, respectively, 3,928,089 bp and 2,580,084 bp, and two megaplasmids pMOL28 and pMOL30 of, respectively, 171,459 bp and 233,720 bp in size. At least 25 loci for heavy-metal resistance (HMR) are distributed over the four replicons. Approximately 67% of the 6,717 coding sequences (CDSs) present in the CH34 genome could be assigned a putative function, and 9.1% (611 genes) appear to be unique to this strain. One out of five proteins is associated with either transport or transcription while the relay of environmental stimuli is governed by more than 600 signal transduction systems. The CH34 genome is most similar to the genomes of other Cupriavidus strains by correspondence between the respective CHR1 replicons but also displays similarity to the genomes of more distantly related species as a result of gene transfer and through the presence of large genomic islands. The presence of at least 57 IS elements and 19 transposons and the ability to take in and express foreign genes indicates a very dynamic and complex genome shaped by evolutionary forces. The genome data show that C. metallidurans CH34 is particularly well equipped to live in extreme conditions and anthropogenic environments that are rich in metals.

OBJECTIVESignificant new data suggest that metabolic disorders such as diabetes, obesity, and atherosclerosis all posses an important inflammatory component. Infiltrating macrophages contribute to both tissue-specific and systemic inflammation, which promotes insulin resistance. The complement cascade is involved in the inflammatory cascade initiated by the innate and adaptive immune response. A mouse genomic F2 cross biology was performed and identified several causal genes linked to type 2 diabetes, including the complement pathway.RESEARCH DESIGN AND METHODSWe therefore sought to investigate the effect of a C3a receptor (C3aR) deletion on insulin resistance, obesity, and macrophage function utilizing both the normal-diet (ND) and a diet-induced obesity mouse model.RESULTSWe demonstrate that high C3aR expression is found in white adipose tissue and increases upon high-fat diet (HFD) feeding. Both adipocytes and macrophages within the white adipose tissue express significant amounts of C3aR. C3aR−/− mice on HFD are transiently resistant to diet-induced obesity during an 8-week period. Metabolic profiling suggests that they are also protected from HFD-induced insulin resistance and liver steatosis. C3aR−/− mice had improved insulin sensitivity on both ND and HFD as seen by an insulin tolerance test and an oral glucose tolerance test. Adipose tissue analysis revealed a striking decrease in macrophage infiltration with a concomitant reduction in both tissue and plasma proinflammatory cytokine production. Furthermore, C3aR−/− macrophages polarized to the M1 phenotype showed a considerable decrease in proinflammatory mediators.CONCLUSIONSOverall, our results suggest that the C3aR in macrophages, and potentially adipocytes, plays an important role in adipose tissue homeostasis and insulin resistance.

X-ray crystal structures of two non-nucleoside analogue inhibitors bound to hepatitis C virus NS5B RNAdependent RNA polymerase have been determined to 2.0 and 2.9 Å resolution. These noncompetitive inhibitors bind to the same site on the protein, ϳ35 Å from the active site. The common features of binding include a large hydrophobic region and two hydrogen bonds between both oxygen atoms of a carboxylate group on the inhibitor and two main chain amide nitrogen atoms of Ser 476 and Tyr 477 on NS5B. The inhibitor-binding site lies at the base of the thumb domain, near its interface with the C-terminal extension of NS5B. The location of this inhibitor-binding site suggests that the binding of these inhibitors interferes with a conformational change essential for the activity of the polymerase. Hepatitis C virus (HCV)1 infects about 3% of the world's human population. HCV infection can develop into chronic hepatitis, which, in some cases, causes cirrhosis of the liver, eventually leading to hepatocellular carcinoma (1). There is no vaccine against HCV currently, and no generally effective therapy for all genotypes of HCV is available. At the present time, the use of recombinant interferon ␣-2a, ␣-2b, "consensus" interferon, and pegylated interferon ␣-2b either in monotherapy or in combination with ribavirin is the only approved therapy available (2). However, limited efficacy and some adverse side effects are associated with these therapies (3). Therefore, the development of HCV-specific antiviral agents is needed urgently.Extensive studies have been done to understand the structures and functions of the individual components of the HCVencoded polyprotein (structural proteins C, E1, and E2 and nonstructural proteins NS2, NS3, NS4A, NS4B, NS5A, and NS5B) (4 -6). Among them, NS2, NS3 protease and helicase, and NS5B RNA-dependent RNA polymerase are essential enzymes for the replication of HCV. The high resolution crystal structures of NS3 protease (7-9) and helicase domains (10, 11) and NS5B polymerase (12-14) have been determined by crystallographic methods in the past 5 years. These enzymes are potential targets for structure-based drug design. The inhibitors of NS3 protease and, in some cases, corresponding structures of NS3 protease/inhibitor complexes have been reported recently (15). In the case of HCV NS5B polymerase, both nucleoside and non-nucleoside inhibitors have been discovered in recent years (16). 3TC (2Ј-deoxy-3Ј-thiacytidine proprietary compound lamivudine) triphosphate has been reported to have a weak inhibitory effect with a 50% inhibitory concentration (IC 50 ) of 180 M (17), whereas numerous non-nucleoside compounds have been documented to possess relatively potent anti-NS5B activity. Examples include specific rhodanines and barbituric acid derivatives, many of which were found to exhibit anti-NS5B activity with IC 50 values below 1 M (18, 19). Classes of dihydroxypyrimidine carboxylic acids and diketoacid derivatives were claimed as well with IC 50 values within the submicromolar range for the latt...

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