Methods for the isolation of viruses from environmental samples

    Viruses are omnipresent and extraordinarily abundant in the microbial ecosystems of water, soil, and sediment. In nearly every reported case for aquatic and porous media environments (soils and sediments) viral abundance exceeds that of co-occurring host populations by 10 to 100 fold. If current estimates based on metagenome DNA sequence data are correct, then viruses represent the largest reservoir of unknown genetic diversity on Earth. Microscopy and molecular genetic tools have been critical to demonstrating that viruses are a dynamic component of microbial ecosystems, capable of significantly influencing the productivity and population biology of their host communities. Moreover, these approaches have begun to describe and constrain the immense genetic diversity of viral communities. A critical first step in the application of many cultivation-independent approaches to virus ecology is obtaining a concentrate of viruses from an environmental sample. Here, methodological details for the isolation and concentration of viruses from water, soil, and aquatic sediment samples are covered in detail.

1.  Large scale tangential-flow filtration of water samples
2.  Small-scale tangential-flow ultrafiltration of water samples  
3.  Extraction of aquatic sediments
4.  Extraction of terrestrial soils
5.  Phytoplankton techniques
6.  Enumeration of viruses and bacteria using SYBR Gold
7.  Casting viral concentrates in agarose plugs
8.  Plaque assay procedures
9.  Phaeocystis globosa culture techniques
10. Further concentrating VCs for PFGE and other techniques
11. Cesium chloride purification of phage concentrates
12. PFGE protocol
13. DNA extraction of aquatic bacteria communitiesMethod%201.htmlMethod%202.htmlMethod%203.htmlMethod%204.htmlMethod%205.htmlMethod%206.htmlMethod%207.htmlMethod%208.htmlMethod%209.htmlMethod%2010.htmlMethod%2011.htmlMethod%2012.htmlMethod%2013.htmlshapeimage_1_link_0shapeimage_1_link_1shapeimage_1_link_2shapeimage_1_link_3shapeimage_1_link_4shapeimage_1_link_5shapeimage_1_link_6shapeimage_1_link_7shapeimage_1_link_8shapeimage_1_link_9shapeimage_1_link_10shapeimage_1_link_11shapeimage_1_link_12