Viral enumeration using cost-effective wet-mount epifluorescence microscopy for aquatic ecosystems and modern microbialites

Abstract

Low-cost and robust viral enumeration is a critical first step toward understanding the global virome. Our method is a deep drive integration providing a window into viral dark matter within aquatic ecosystems. We enumerated the viruses within Green Lake and Great Salt Lake microbialites, EPS, and water column. The entire weight of all the viruses in Green Lake and Great Salt Lake are ~598 g and ~2.2 kg, respectively.

Keywords: Fayetteville Green Lakes, NY; Great Salt Lake, UT; bacteriophage (phage); epifluorescence microscopy; microbialites; stromatolites; thrombolites; viruses.

Fig 1

Flow diagram of EFM protocol. This diagram provides a detailed methodological walk-through of the preparation of water, microbial mat, and EPS samples.

Fig 2

Viral enumeration of GSL and FGL. EPS and whole mat VLPs are expressed as g⁻¹ vs mL⁻¹ for water samples. All images are under 100× oil immersion with a scale bar equal to 200 pixels or 10 µm. All images were converted to negatives to increase the visibility of VLPs. (A) Average VLP concentrations for water samples with representative EFM images. (B) Average VLP concentrations for EPS samples with representative EFM images. (C) Average VLP concentrations for mat samples with representative EFM images.