methanobrevibacter smithii microorganisms, 3d , the predominant archaeon in the microbiota of the human

archaea archeon flora gastrointestinal gut human intestinal intestine methanobacteriaceae methanobrevibacter microbe microbiota microflora prokaryote sem 3d illustration bacteria microorganism medicine medical background bacterial biology cell coli disease epidemic health ill illness infection life macro micro microbiology microscope microscopic organism research science scientific sick virus constipation methanogen methanogenic methane