Diversity and physiology of methanogenic Archaea 16S ribosomal RNA sequence analyses classify methanogen into seven major groups All methanogens use NH4* as a nitrogen source A few species can fix molecular nitrogen Nickel is a trace metal required by all methanogens, it is a component of coenzyme Factor430 Iron and Cobalt are also important for methanogens Pictures on the left: morphological diversity of methanogensDiversity and Physiology of Methanogenic Archaea 16S ribosomal RNA sequence analyses classify methanogen into seven major groups All methanogens use NH4 + as a nitrogen source A few species can fix molecular nitrogen Nickel is a trace metal required by all methanogens, it is a component of coenzyme Factor430 Iron and Cobalt are also important for methanogens. Pictures on the left: morphological diversity of methanogens