Characterization of airborne viromes in cheese production plants.
AIMS
To characterize airborne virus-like particles isolated from two cheese production plants in order to reveal their complexity in terms of viral communities and microbial genes potentially mobilized by viruses.


METHODS AND RESULTS
Airborne virus-like particles have been isolated from Grana Padano and Gorgonzola PDO cheese production plants and ripening cellars. A shotgun metagenomics analysis of the isolated viromes highlighted a high complexity of the viral communities both in terms of viral taxonomy and phage-host associations. Bacterial reads in each of the viromes were confirmed to be abundant and their taxonomy appeared to be associated with the environmental parameters and the technological processes that characterize the sampling area. Antibiotic resistance genes have been identified in each virome thus confirming that phages could be involved in the mobilization of antimicrobial resistances among bacterial populations. Interestingly human viruses were also identified even if the contamination source was not revealed.


CONCLUSIONS
The environmental conditions, which are imposed by the technology of the dairy process, seam to shape the viral populations as a consequence of the adaptation of microbial taxa to those environments. The identification of sequences belonging to Legionella pneumophila and to the human papillomavirus, raised some considerations about the safety of cheese-ripening cellars.


SIGNIFICANCE AND IMPACT OF THE STUDY
In conclusion, the analysis of the dairy airborne viromes, has revealed a high complexity of the viral communities even if the environments where the samples were collected were confined environments. Metagenomics of airborne viral population could be a promising monitoring tool for the biological characterization of dairy environments.
['Colombo|S|S|', 'Arioli|S|S|', 'Gargari|G|G|', 'Neri|E|E|', 'Della Scala|G|G|', 'Mora|D|D|http://orcid.org/0000-0002-6692-9301']
D001419:Bacteria D001435:Bacteriophages D002611:Cheese D004352:Drug Resistance, Microbial D004784:Environmental Monitoring D005525:Food-Processing Industry D006801:Humans D056186:Metagenomics D014780:Viruses
virome cheese virus-like particles metagenomics antibiotic resistance gene