TY - JOUR
T1 - A non-methanogenic archaeon within the order Methanocellales
AU - Suzuki, Shino
AU - Ishii, Shun’ichi
AU - Chadwick, Grayson L.
AU - Tanaka, Yugo
AU - Kouzuma, Atsushi
AU - Watanabe, Kazuya
AU - Inagaki, Fumio
AU - Albertsen, Mads
AU - Nielsen, Per H.
AU - Nealson, Kenneth H.
N1 - © 2024. The Author(s).
PY - 2024/12
Y1 - 2024/12
N2 - Serpentinization, a geochemical process found on modern and ancient Earth, provides an ultra-reducing environment that can support microbial methanogenesis and acetogenesis. Several groups of archaea, such as the order Methanocellales, are characterized by their ability to produce methane. Here, we generate metagenomic sequences from serpentinized springs in The Cedars, California, and construct a circularized metagenome-assembled genome of a Methanocellales archaeon, termed Met12, that lacks essential methanogenesis genes. The genome includes genes for an acetyl-CoA pathway, but lacks genes encoding methanogenesis enzymes such as methyl-coenzyme M reductase, heterodisulfide reductases and hydrogenases. In situ transcriptomic analyses reveal high expression of a multi-heme c-type cytochrome, and heterologous expression of this protein in a model bacterium demonstrates that it is capable of accepting electrons. Our results suggest that Met12, within the order Methanocellales, is not a methanogen but a CO2-reducing, electron-fueled acetogen without electron bifurcation.
AB - Serpentinization, a geochemical process found on modern and ancient Earth, provides an ultra-reducing environment that can support microbial methanogenesis and acetogenesis. Several groups of archaea, such as the order Methanocellales, are characterized by their ability to produce methane. Here, we generate metagenomic sequences from serpentinized springs in The Cedars, California, and construct a circularized metagenome-assembled genome of a Methanocellales archaeon, termed Met12, that lacks essential methanogenesis genes. The genome includes genes for an acetyl-CoA pathway, but lacks genes encoding methanogenesis enzymes such as methyl-coenzyme M reductase, heterodisulfide reductases and hydrogenases. In situ transcriptomic analyses reveal high expression of a multi-heme c-type cytochrome, and heterologous expression of this protein in a model bacterium demonstrates that it is capable of accepting electrons. Our results suggest that Met12, within the order Methanocellales, is not a methanogen but a CO2-reducing, electron-fueled acetogen without electron bifurcation.
UR - http://www.scopus.com/inward/record.url?scp=85195922863&partnerID=8YFLogxK
U2 - 10.1038/s41467-024-48185-5
DO - 10.1038/s41467-024-48185-5
M3 - Journal article
C2 - 38871712
AN - SCOPUS:85195922863
SN - 2041-1723
VL - 15
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 4858
ER -