RT Journal Article
SR Electronic
T1 Isolation of an archaeon at the prokaryote-eukaryote interface
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 726976
DO 10.1101/726976
A1 Hiroyuki Imachi
A1 Masaru K. Nobu
A1 Nozomi Nakahara
A1 Yuki Morono
A1 Miyuki Ogawara
A1 Yoshihiro Takaki
A1 Yoshinori Takano
A1 Katsuyuki Uematsu
A1 Tetsuro Ikuta
A1 Motoo Ito
A1 Yohei Matsui
A1 Masayuki Miyazaki
A1 Kazuyoshi Murata
A1 Yumi Saito
A1 Sanae Sakai
A1 Chihong Song
A1 Eiji Tasumi
A1 Yuko Yamanaka
A1 Takashi Yamaguchi
A1 Yoichi Kamagata
A1 Hideyuki Tamaki
A1 Ken Takai
YR 2019
UL http://biorxiv.org/content/early/2019/08/06/726976.abstract
AB The origin of eukaryotes remains enigmatic. Current data suggests that eukaryotes may have risen from an archaeal lineage known as “Asgard archaea”. Despite the eukaryote-like genomic features found in these archaea, the evolutionary transition from archaea to eukaryotes remains unclear due to the lack of cultured representatives and corresponding physiological insight. Here we report the decade-long isolation of a Lokiarchaeota-related Asgard archaeon from deep marine sediment. The archaeon, “Candidatus Prometheoarchaeum syntrophicum strain MK-D1”, is an anaerobic, extremely slow-growing, small cocci (∼550 nm), that degrades amino acids through syntrophy. Although eukaryote-like intracellular complexities have been proposed for Asgard archaea, the isolate has no visible organella-like structure. Ca. P. syntrophicum instead displays morphological complexity – unique long, and often, branching protrusions. Based on cultivation and genomics, we propose an “Entangle-Engulf-Enslave (E3) model” for eukaryogenesis through archaea-alphaproteobacteria symbiosis mediated by the physical complexities and metabolic dependency of the hosting archaeon.