Gut microbiome of ICU patients
DNA isolation was performed using the QIAamp DNA Stool Kit protocol (Qiagen; Hilden, Germany) according to the manufacturers protocol. Sequencing of 16S rRNA gene was performed using Ion 16S Metagenomics Kit (Life Technologies; Carlsbad, CA, USA) on the Ion Torrent Personal Genome Machine (PGM) platform (Life Technologies; Carlsbad, CA, USA).