FEMS Microbiol Lett 1992,74(2–3):271–276.selleck inhibitor CrossRefPubMed 50. Sambrook J, Fritsch EF, Maniatis T: Molecular Cloning: a Laboratory Manual. 2 Edition New York, NY: Cold Spring Harbour Laboratory Press 1989. 51. Altschul SF, Madden TL, Schaffer

AA, Zhang J, Zhang Z, Miller W, Lipman DJ: Gapped BLAST and PSI-BLAST: a new generation of protein database search programs. Nucleic Acids Res 1997,25(17):3389–3402.CrossRefPubMed 52. Brickman E, Beckwith J: Analysis of the regulation of Escherichia coli alkaline phosphatase synthesis using deletions and ICG-001 phi80 transducing phages. J Mol Biol 1975,96(2):307–316.CrossRefPubMed Authors’ contributions TG drafted the manuscript, participated in design of the study and performed all experiments that are not credited

to the additional authors, listed below. PF generated multiple strains (PCF# strains) and plasmids used in the study, participated in sequencing phoBR, participated in design of the study and critically reviewed the manuscript. LE isolated strains BR1 and BR9, performed primer extension analysis, participated in sequencing phoBR and pstSCAB-phoU, and participated in design of the study. NW generated strain NW201 and NW202, measured pstC::uidA expression and participated in sequencing of pstSCAB-phoU. GS conceived of the study and participated in the R788 price design and coordination of the study.”
“Background Approximately 130 million people are infected worldwide by Hepatitis C Virus (HCV) [1]. Almost 80% of infected patients develop a chronic hepatitis that can in the long term evolve either to liver cirrhosis or hepatocellular carcinoma. Unfortunately, no vaccine is currently available

to prevent new infections and the current treatments are not fully efficient [2]. HCV is an enveloped RNA virus mainly targeting liver cells by a mechanism that has yet to be elucidated. For a long time, it has been difficult to study the different steps of the HCV life cycle because of the difficulties in propagating this virus in cell culture. However, a major step in investigating HCV entry was achieved in the development of pseudotyped particles (HCVpp), consisting of native HCV envelope glycoproteins, E1 and E2, assembled onto retroviral core second particles [3–5]. More recently, the development of a cell culture system allowing an efficient amplification of HCV (HCVcc) has also been reported [6–8]. This cell culture system allows the study of the whole life cycle of HCV and, together with HCVpp, also permits the characterization of HCV entry mechanisms. Although the early steps of viral entry have yet to be elucidated, accumulated data suggest several cell surface-expressed molecules as entry factors for HCV (reviewed in [9]). Among these molecules, the tetraspanin CD81 has been shown to play a key role in HCV entry, acting during a post-attachment step [10, 11].