Gambusia marshi fish gut viral metagenome sample from Cuatro Cienegas Basin
To extract viral particles from intestinal content of the three fish species (Hemichromis guttatus, Gambusia marshi, and Cyprinodon bifasciatus), 200  l of intestinal content was added to conical screw-cap tubes containing 100 mg of 150-212  m glass beads (Sigma, USA), chloroform (100  l), and PBS up to 1 ml. Samples were homogenized in a bead beater (Biospec Products, USA), centrifuged 10 minutes at 2,000 x g. Supernatants were recovered and filtered in Spin-X 22  m pore filters (Costar, NY, USA) at 5,000 x g during 10-20 minutes. Filtered samples were treated with Turbo DNAse (Ambion, USA) and RNAse (Sigma, USA) and extraction continued as water samples.