Abstract
Fer.men.ti.micr.ar.chae'um. L. gen. neut. n.
fermenti
, of a fermentation process; N.L. masc. adj.
micros
, small [probably better: micrus]; N.L. neut. n.
archaeum
, ancient one, archaeon; from Gr. adj.
archaîos ‐a ‐on
, ancient; N.L. neut. n.
Fermentimicrarchaeum
, a small archaeon performing fermentation processes.
Microcaldota / Microcaldia / Candidatus Fermentimicrarchaeales / Candidatus Fermentimicrarchaeaceae / Candidatus Fermentimicrarchaeum
The genus
Candidatus
Fermentimicrarchaeum was established based on complete genome sequence assembled from a freshwater lake sediment metagenome.
Ca
. Fermentimicrarchaeum is phylogenetically affiliated with the phylum
Microcaldota
(previously known as
Candidatus
Micrarchaeota) of the archaeal DPANN superphylum. Analysis of the 1.2 Mb genome of
Ca
. Fermentimicrarchaeum suggests that, contrary to the ARMAN group of
Microcaldota
and most DPANN members, this organism has complete glycolytic pathways and ATP generation mechanisms in substrate phosphorylation, the capacities to utilize some sugars and amino acids as substrates, and pathways for
de novo
nucleotide biosynthesis but lacks an aerobic respiratory chain. We suppose that
Ca
. Fermentimicrarchaeum is a free‐living scavenger rather than an obligate parasite or symbiont, and its functional role in lake sediments consists of the fermentation of low molecular weight organic compounds. 16S rRNA gene sequences and metagenome‐assembled genomes affiliated with
Ca
. Fermentimicrarchaeum were recovered from freshwater lake sediments and soils.
DNA G
+
C content (mol%)
: 46.4–48.5 (genome sequence).
Type species
:
Candidatus
Fermentimicrarchaeum limneticum
Kadnikov et al. 2020, CL3.