The article discusses the reclassification of methanogens based on 16S rRNA sequence analysis. Methanogens, which produce methane, were previously classified as a single family, but recent studies using 16S rRNA comparative cataloging have revealed a more complex phylogenetic structure. The analysis shows that methanogens form a distinct group, phylogenetically distant from typical bacteria. This new classification is based on the 16S rRNA sequence homology, which provides a more accurate reflection of their evolutionary relationships. The study outlines a new taxonomic treatment for methanogens, dividing them into three orders: Methanobacteriales, Methanococcales, and Methanomicrobiales. Each order contains one or more families, genera, and species. The new classification is supported by various data, including cell wall composition, lipid distribution, intermediary metabolism, and nucleic acid composition. The methanogens are shown to have distinct cell wall structures, with some species having a unique type of cell wall polymer called pseudomurein, which differs from the typical bacterial murein. The article also presents the proposed new taxonomic scheme, which includes three orders, four families, and seven genera. The classification is based on the 16S rRNA sequence data, which reveals the phylogenetic relationships among the methanogens. The new classification is supported by the distinct 16S rRNA sequences of the various methanogen species, which indicate their unique evolutionary history. The study concludes that the methanogens represent a coherent phylogenetic grouping, distinct from other typical bacteria. The new classification provides a more accurate and comprehensive understanding of the relationships among the methanogens, and it reflects their unique biological characteristics. The findings highlight the importance of molecular data in bacterial classification and underscore the need for a more accurate and systematic approach to understanding microbial diversity.The article discusses the reclassification of methanogens based on 16S rRNA sequence analysis. Methanogens, which produce methane, were previously classified as a single family, but recent studies using 16S rRNA comparative cataloging have revealed a more complex phylogenetic structure. The analysis shows that methanogens form a distinct group, phylogenetically distant from typical bacteria. This new classification is based on the 16S rRNA sequence homology, which provides a more accurate reflection of their evolutionary relationships. The study outlines a new taxonomic treatment for methanogens, dividing them into three orders: Methanobacteriales, Methanococcales, and Methanomicrobiales. Each order contains one or more families, genera, and species. The new classification is supported by various data, including cell wall composition, lipid distribution, intermediary metabolism, and nucleic acid composition. The methanogens are shown to have distinct cell wall structures, with some species having a unique type of cell wall polymer called pseudomurein, which differs from the typical bacterial murein. The article also presents the proposed new taxonomic scheme, which includes three orders, four families, and seven genera. The classification is based on the 16S rRNA sequence data, which reveals the phylogenetic relationships among the methanogens. The new classification is supported by the distinct 16S rRNA sequences of the various methanogen species, which indicate their unique evolutionary history. The study concludes that the methanogens represent a coherent phylogenetic grouping, distinct from other typical bacteria. The new classification provides a more accurate and comprehensive understanding of the relationships among the methanogens, and it reflects their unique biological characteristics. The findings highlight the importance of molecular data in bacterial classification and underscore the need for a more accurate and systematic approach to understanding microbial diversity.