Spike-mediated viral membrane fusion is inhibited by a specific anti-IFITM2 monoclonal antibody

The early steps of viral infection involve protein complexes and structural lipid rearrangements which characterize the peculiar strategies of each virus to invade permissive host cells. Members of the human immune-related interferon-induced transmembrane (IFITM) protein family have been described as inhibitors of the entry of a broad range of viruses into the host cells. Recently, it has been shown that SARS-CoV-2 is able to hijack IFITM2 for efficient infection. Here, we report the characterization of a newly generated specific anti-IFITM2 mAb able to impair Spike-mediated internalization of SARS-CoV-2 in host cells and, consequently, to reduce the SARS-CoV-2 cytopathic effects and syncytia formation. Furthermore, the anti-IFITM2 mAb reduced HSVs- and RSV-dependent cytopathic effects, suggesting that the IFITM2-mediated mechanism of host cell invasion might be shared with other viruses besides SARS-CoV-2. These results show the specific role of IFITM2 in mediating viral entry into the host cell and its candidacy as a cell target for antiviral therapeutic strategies

Sugar oxidoreductases and veratryl alcohol oxidase as related to lignin degradation

Properties of cellobiose:quinone oxidoreductase (CBQ), cellobiose dehydrogenase (CDH), glyoxal oxidase (GLOX), glucose oxidases and veratryl alcohol oxidase (VAO) are reviewed. There is strong evidence that CDH reduces quinones, phenoxy and cation radicals. Glucose oxidases (glucose 1-oxidase and pyranose 2-oxidase) and VAO have been less investigated but evidence for reduction of the above compounds is accumulating. Pyranose oxidase, glyoxal oxidase and VAO are very important for hydrogen peroxide production by white-rot fungi. CDH is only produced on cellulose or on wood, whereas pyranose oxidase and VAO are produced both on wood and on rich glucose media suggesting that the lignin degrading white-rot fungi may use different quinone and radical reducing enzymes to regulate lignin polymerization/depolymerization depending on the substrate and cultivation conditions. Intracellular quinone reductases are also produced. Whether brown-rot fungi in general produce CBQ/CDH or VAO is not clear. The Fe(III) reducing ability of both CDH and certain phenolate compounds agree with the rapid depolymerization of cellulose by brown-rot fungi. The interaction of Fe(III) reduction with the hydrogen peroxide producing system in white-rot and brown-rot fungi requires more investigation. © 1997 Elsevier Science B.V

Reduction of phenol content and toxicity in olive oil mill waste waters with the ligninolytic fungus Pleurotus ostratus

Olive oil mill waste waters (OMW) constitute a major environmental problem because of the large amount produced and the toxicity of the phenolic compounds present. Several of these aromatic compounds can be assimilated to many of the components of lignin. Only few microorganisms, mainly “white-rot” basidiomycete, are able to degrade lignin by means of oxidative reactions catalysed by phenol oxidases and peroxidases. Both the low degree of specificity which characterizes these enzymes, and the structural relationships of many aromatic pollutants with the natural substrates of the enzymes, have suggested the use of ligninolytic organisms and of their enzymes for the treatment of these kinds of substrates. This paper investigates the ability of the “white-rot” basidiomycete Pleurotus ostreatus and particularly of the phenol oxidases it produces in the detoxification of OMW phenol compounds. Treatment of OMW with purified phenol oxidase showed a significant reduction of phenolic content, but no decrease of its toxicity was observed when tested on Bacillus cereus. Otherwise, the effect of processing OMW with the entire microorganism resulted in a noticeable detoxification of the waste with concomitant abatement of the phenol content