The envelope glycoproteins E1 and E2 of Sindbis virus are palmitoylated at cysteine residues within their transmembrane domains (E1 at position 430, and E2 at positions 388 and 390). Here, we investigated the in vitro membrane fusion activity of Sindbis virus variants (derived from the Toto 1101 infectious clone), in which the E1 C430 and/or E2 C388/390 residues had been substituted for alanine...

Hepatitis C virus (HCV) is a major cause of chronic hepatitis worldwide. Studies of the early steps of HCV infection have been hampered by the lack of convenient in vitro or in vivo models. Although several cell-surface molecules that mediate the binding of HCV envelope proteins to target cells have been identified, mechanisms of viral entry into human hepatocytes are still poorly understood. V...

A chord diagram is a set of chords of a circle such that no pair of chords has a common endvertex. A pair of chords is called a crossing if the two chords intersect. A chord diagram E is called nonintersecting if E contains no crossing. For a chord diagram E having a crossing S = {x1x3, x2x4}, the expansion of E with respect to S is to replace E with E1 = (E \S)∪{x2x3, x4x1} or E2 = (E \S)∪{x1x...

Replication of bovine papillomavirus type 1 DNA absolutely requires the viral transcription factor E2 as well as the initiator E1, although E1 alone has all the activities expected of an initiator protein. E1 assembles on the DNA in a stepwise fashion and undergoes a transition in activities from site-specific DNA-binding protein to mobile helicase. Complex assembly is assisted by the viral tra...

In this study, we examined the expression of hepatitis C virus (HCV) components in hepatocytes and peripheral blood mononuclear cells (PBMC) from patients positive for anti-HCV antibodies and negative for serum HCV-RNA. The samples obtained from 25 randomly selected patients (13 of 25 patients showed no histological evidences of chronic hepatitis and had normal serum ALAT and GGTP levels) were ...

Hepatitis C virus (HCV) infection is a significant public health problem with over 170,000,000 chronic carriers and infection rates increasing worldwide. Chronic HCV infection is one of the leading causes of hepatocellular carcinoma which was estimated to result in ∼10,000 deaths in the United States in the year 2011. Current treatment options for HCV infection are limited to PEG-ylated interfe...

The kinetics of the E2 --> E1 conformational change of unphosphorylated Na+,K+-ATPase was investigated via the stopped-flow technique using the fluorescent label RH421 (pH 7.4, 24 degrees C). The enzyme was pre-equilibrated in a solution containing 25 mM histidine and 0.1 mM EDTA to stabilize the E2 conformation. When rabbit enzyme was mixed with 130 mM NaCl alone or with 130 mM NaCl and varyin...

In this paper we introduce a logic for graph, where the domain is the edges, not the vertices. Such logic behaves differently from the usual graph logic, where the domain is the vertices, because reachability can be expressed in monadic NP in this logic, while it cannot in the standard graph logic. We establish that in this logic to express a path of length 2k or less, quantifier rank k is nece...

Human papillomavirus (HPV) DNA replication is initiated by recruitment of the E1 helicase by the E2 protein to the viral origin. Screening of our corporate compound collection with an assay measuring the cooperative binding of E1 and E2 to the origin identified a class of small molecule inhibitors of the protein interaction between E1 and E2. Isothermal titration calorimetry and changes in prot...