0 avis
Flow Cytometry Sorting to Separate Viable Giant Viruses from Amoeba ă Co-culture Supernatants
Archive ouverte
International audience. Flow cytometry has contributed to virology but has faced many drawbacks ă concerning detection limits, due to the small size of viral particles. ă Nonetheless, giant viruses changed many concepts in the world of ă viruses, as a result of their size and hence opened up the possibility ă of using flow cytometry to study them. Recently, we developed a high ă throughput isolation of viruses using flow cytometry and protozoa ă co-culture. Consequently, isolating a viral mixture in the same sample ă became more common. Nevertheless, when one virus multiplies faster than ă others in the mixture, it is impossible to obtain a pure culture of the ă minority population. Here, we describe a robust sorting system, which ă can separate viable giant virus mixtures from supernatants. We tested ă three flow cytometry sorters by sorting artificial mixtures. Purity ă control was assessed by electron microscopy and molecular biology. As ă proof of concept, we applied the sorting system to a co-culture ă supernatant taken from a sample containing a viral mixture that we ă couldn't separate using end point dilution. In addition to isolating the ă quick-growing Mimivirus, we sorted and re-cultured a new, slow-growing ă virus, which we named Cedratvirus. The sorting assay presented in this ă paper is a powerful and versatile tool for separating viral populations ă from amoeba co-cultures and adding value to the new field of flow ă virometry.