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The molecular mechanism of entry of herpesviruses requires a multicomponent fusion system. Cell invasion by Herpes simplex virus (HSV) requires four virally encoded glycoproteins: namely gD, gB and gH/gL. The role of gB has remained elusive until recently when the crystal structure of HSV-1 gB became available and the fusion potential of gB was clearly demonstrated. Although much information on gB structure/function relationship has been gathered in recent years, the elucidation of the nature of the fine interactions between gB fusion loops and the membrane bilayer may help to understand the precise molecular mechanism behind herpesvirus-host cell membrane fusion. Here, we report the first biophysical study on the two fusion peptides of gB, with a particular focus on the effects determined by both peptides on lipid bilayers of various compositions. The two fusion loops constitute a structural subdomain wherein key hydrophobic amino acids form a ridge that is supported on both sides by charged residues. When used together the two fusion loops have the ability to significantly destabilize the target membrane bilayer, notwithstanding their low bilayer penetration when used separately. These data support the model of gB fusion loops insertion into cholesterol enriched membranes.

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Multiwalled carbon nanotube sheets of relatively large area have been grown on a sapphire substrate by chemical vapor deposition at the substrate temperature of 500 and 750°C. The photoconductivity measurements, performed under white light and monochromatic radiation in the ultraviolet–visible–near infrared region, show that the highly defective sample grown at 500°C has a higher photosensitivity, thus revealing the crucial role of structural defects in determining the overall photoresponse of the nanotube’s sheets. The spectral photoresponse of these nanostructured films increases with the increase in photon energy, and is strongly correlated to the absorbance. The photoconductivity properties of these materials are favorable in potential development of large area light sensors as well as optoelectronic nanodevices.