Utilization of interferometric light microscopy for the rapid analysis of virus abundance in a river

摘要

There is a constant need for direct counting of biotic nanoparticles such as viruses to unravel river functioning. We used, for the first time in freshwater, a new method based on interferometry differentiating viruses from other particles such as membrane vesicles. In the French Marne River, viruses represented between 42 and 72% of the particles. A spring monitoring in 2014 revealed their increase ( 2.1 x 10(7) to 2.1 x 10(8) mL(-1)) linked to an increase in algal biomass and diversity of bacterial plankton. Predicted virus size distributions were in agreement with transmission electron microscopy analysis suggesting a dominance of large viruses (>= 60 nm). (C) 2017 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.