정만영

[논문] Adaptive traits of Nitrosocosmicus clade ammonia-oxidizing archaea

Environmental Microbiology

4.3

1462-2912

15(11)

SCIE

Nitrification is a core process in the global nitrogen (N) cycle mediated by ammonia-oxidizing microorganisms, including ammonia-oxidizing archaea (AOA) as a key player. Although much is known about AOA abundance and diversity across environments, the genetic drivers of the ecophysiological adaptations of the AOA are often less clearly defined. This is especially true for AOA within the genus Nitrosocosmicus, which have several unique physiological traits (e.g., high substrate tolerance, low substrate affinity, and large cell size). To better understand what separates the physiology of Nitrosocosmicus AOA, we performed comparative genomics with genomes from 39 cultured AOA, including five Nitrosocosmicus AOA. The absence of a canonical high-affinity type ammonium transporter and typical S-layer structural genes was found to be conserved across all Nitrosocosmicus AOA. In agreement, cryo-electron tomography confirmed the absence of a visible outermost S-layer structure, which has been observed in other AOA. In contrast to other AOA, the cryo-electron tomography highlighted the possibility that Nitrosocosmicus AOA may possess a glycoprotein or glycolipid-based glycocalyx cell covering outer layer. Together, the genomic, physiological, and metabolic properties revealed in this study provide insight into niche adaptation mechanisms and the overall ecophysiology of members of the Nitrosocosmicus clade in various terrestrial ecosystems.

Saem Han, Seongwook Kim, Christopher J. Sedlacek, Adeel Farooq, Chihong Song, Sujin Lee, Shurong Liu, Nicolas Brüggemann, Lena Rohe, Miye Kwon, Sung-Keun Rhee, Man-Young Jung

2024.11.

https://doi.org/10.1128/mbio.02169-24