S0001_2017_2
DNA extractions for metagenomic analysis were based on a previously described method (Alcamn-Arias et al., 2018). Filters were resuspended in lysis buffer containing xanthogenate buffer (1% potassium ethyl xanthogenate). Next, SDS was added to 1% and then the mixture was incubated at 65 C for 2 hours. DNA was extracted with phenol:chloroform:isoamyl alcohol (25:24:1) and then the residual phenol was eliminated with chloroform:isoamyl alcohol (24:1). For each sample, approximately >500 ng of total DNA was sent for Illumina sequencing on the NovaSeq 6000 platform with a read length of 150 bp (paired-end).