ABSTRACT
The bacteriophage T4 DNA replisome is a complex dynamic system employing a variety of proteins to orchestrate the synthesis of DNA on both the leading and lagging strands. Assembly of the protein complexes responsible for DNA synthesis and priming requires the coordination of transient biomolecular interactions. This interplay of proteins has been dissected through the use of small molecules including fluorescent probes and crosslinkers, enabling the development of a complex dynamic structural and kinetic model for DNA polymerase holoenzyme assembly and primosome formation.
Subject(s)
Bacteriophage T4/genetics , Bacteriophage T4/metabolism , DNA Replication , DNA-Directed DNA Polymerase/metabolism , Molecular Biology/methods , Multienzyme Complexes/metabolism , Cross-Linking Reagents/chemistry , DNA-Directed DNA Polymerase/chemistry , Fluorescence , Spectrometry, Fluorescence/methodsABSTRACT
Several experimental studies on hepatitis C virus (HCV) have suggested the envelope glycoprotein E2 as a key antigen for an effective vaccine against the virus. Knowledge of its structure, therefore, would present a significant step forward in the fight against this disease. This paper reports the application of fold recognition methods in order to produce a model of the HCV E2 protein. Such investigation highlighted the envelope protein E of Tick Borne Encephalitis virus as a possible template for building a model of HCV E2. Mapping of experimental data onto the model allowed the prediction of a composite interaction site between E2 and its proposed cellular receptor CD81, as well as a heparin binding domain. In addition, experimental evidence is provided to show that CD81 recognition by E2 is isolate or strain specific and possibly mediated by the second hypervariable region (HVR2) of E2. Finally, the studies have also allowed a rough model for the quaternary structure of the envelope glycoproteins E1 and E2 complex to be proposed. Proteins 2000;40:355-366.
