TheNitrosopumilus maritimusCdvB, but Not FtsZ, Assembles into Polymers

Abstract

Euryarchaeota and Crenarchaeota are two major phyla of archaea which use distinct molecular apparatuses for cell division. Euryarchaea make use of the tubulin-related protein FtsZ, while Crenarchaea, which appear to lack functional FtsZ, employ the Cdv (cell division) components to divide. Ammonia oxidizing archaeon (AOA) Nitrosopumilus maritimus belongs to another archaeal phylum, the Thaumarchaeota, which has both FtsZ and Cdv genes in the genome. Here, we used a heterologous expression system to characterize FtsZ and Cdv proteins from N. maritimus by investigating the ability of these proteins to form polymers. We show that one of the Cdv proteins in N. maritimus, the CdvB (Nmar_0816), is capable of forming stable polymers when expressed in fission yeast. The N. maritimus CdvB is also capable of assembling into filaments in mammalian cells. However, N. maritimus FtsZ does not assemble into polymers in our system. The ability of CdvB, but not FtsZ, to polymerize is consistent with a recent finding showing that several Cdv proteins, but not FtsZ, localize to the mid-cell site in the dividing N. maritimus. Thus, we propose that it is Cdv proteins, rather than FtsZ, that function as the cell division apparatus in N. maritimus.

Candidatus Nitrosocaldus cavascurensis, an Ammonia Oxidizing, Extremely Thermophilic Archaeon with a Highly Mobile Genome

“…The Ca. N. cavascurensis CdvB paralogs (as all other thaumarchaeal CdvBs) all share the core ESCRT-III with the crenarchaeal CdvB sequences, contain a putative (but rather unconvincing) MIM2 motif necessary for interacting with CdvC in Crenarchaeota, while they all lack the C-terminal winged-helix domain responsible for interacting with CdvA ( Samson et al, 2011 ; Ng et al, 2013 ). Interestingly, one of the Ca.…”

Enrichment and Genome Sequence of the Group I.1a Ammonia-Oxidizing Archaeon “Ca. Nitrosotenuis uzonensis” Representing a Clade Globally Distributed in Thermal Habitats

“…As other genome-sequenced thaumarchaeotes, the enriched AOA encodes homologues of both crenarchaeotal ( cdvABC ) and euryarchaeotal/bacterial ( ftsZ ) cell division machinery components (Table S9 in File S1 ) [ 5 , 69 ]. In N. maritimus the ESCRTIII-related Cdv-system has been demonstrated to be the primary division system, while the role of FtsZ remains unknown [ 70 , 71 ]. Recently, an additional distant tubulin homologue was identified in the genomes of each “ Ca .…”

Thermal adaptation of mesophilic and thermophilic FtsZ assembly by modulation of the critical concentration

“…The Cdv proteins are homologous with components of the eukaryotic endosomal sorting complex required for transport (ESCRT), which participates in membrane bending and scission functions, including cytokinesis [ 10 ]. In mesophilic Nitrosopumilus maritimus , a member of archaeal phylum Thaumarcheaota, both FtsZ and the Cdv proteins are found but only the latter has been proposed to work in cell division [ 11 , 12 ]. Thus, prokaryotic cell division functions through a combined mechanism of protein-condensation followed by a constriction of the cell membrane, regardless of the factors involved or the environmental temperature.…”