Mehle, A. | bioRxiv Science

bioRxiv2018

Differential splicing of ANP32A in birds alters its ability to stimulate RNA synthesis by restricted influenza polymerase

Adaptation of viruses to their host can result in specialization and a restricted host range. Species-specific polymorphisms in the influenza virus polymerase restrict its host range during transmission from birds to mammals. ANP32A was recently been identified as a cellular co-factor impacting polymerase adaption and activity. Avian influenza polymerases require ANP32A containing an insertion resulting from an exon duplication uniquely encoded in birds. Here we find that natural splice variants surrounding this exon create avian ANP32A proteins with distinct effects on polymerase activity. We demonstrate species-independent direct interactions between all ANP32A variants and the PB2 polymerase subunit. This interaction is enhanced in the presence of viral genomic RNA. In contrast, only avian ANP32A restored ribonucleoprotein complex assembly for a restricted polymerase by enhancing RNA synthesis. Our data suggest that ANP32A splicing variation amongst birds differentially impacts viral replication, polymerase adaption, and the potential of avian hosts to be reservoirs.

microbiology↗

bioRxiv2017

Photocatalytic disinfection of surfaces with copper doped TiO2 nanotube coatings illuminated by ceiling mounted fluorescent lights

High economic burden is associated with foodborne illnesses. Different disinfection methods are therefore employed in food processing industry; such as use of ultraviolet light or usage of surfaces with copper-containing alloys. However, all the disinfection methods currently in use have some shortcomings. Here we show that copper doped TiO2 nanotubes deposited on existing surfaces and illuminated with ceiling mounted fluorescent lights or additional low power light emitting diodes can be employed for an economical and permanent disinfection of surfaces.\n\nWe deposited the nanotubes on various surfaces: polyethylene terephatlate, polystyrene, and aluminum oxide, where they could withstand repeated washings with neutral, alkaline or acidic medium. Here we show that the polymer surfaces coated with the nanotubes and innoculated with 107 bacteria, illuminated with ceiling mounted fluorescent lights retard the growth of Listeria Innocua by up to 99% in seven hours of exposure to the fluorescent lights, compared to a control surface. The disinfection properties of the surfaces depend mainly on the temperature difference of the surface and the dew point, where for maximum effectiveness of the photocatalytic effect the difference should be at least 2.5 degrees celsius.\n\nUsage of one dimensional nanomaterials, such as TiO2 nanotubes, offers a promising low cost alternative to current disinfection methods, since illumination of surfaces with common fluorescent lights is sufficient to photo-excite the nanotubes, which sequentially produce microbicidal hydroxyl radicals. Future use of such surfaces with antibacterial nano-coating and resulting sterilizing effect holds promise for such materials to be used in different environments or in better control of critical control points in food production as well as an improved biosecurity during the food manufacturing process.

bioengineering↗