The planctomycetes: emerging models for microbial ecology, evolution and cell biology

“Finally, planctomycetes are a distinct bacterial group from proteobacteria (Fuerst 1995; Jenkins and Fuerst 2001).”

“Planctomycetes are not planktonic fungi but a monophyletic group of Bacteria drawing increasing interest for microbial ecologists as well as evolutionary and cell biologists (12).”

“As mentioned before, anammox bacteria divide by constrictive binary fission as opposed to other known Planctomycetes that divide by budding [Fuerst, 1995].”

“They may also play a significant role in nutrient cycling processes in marine environments by the mineralization of marine snow particles [8, 15].”

“They may have been lost during ¢ltration of the sample, being relatively large bacteria which are often found attached to the surfaces of other organisms [19,27].”

“The latter results in a cell cycle that is characterized by motile and sessile morphotypes similar to Caulobacter crescentus [14-17].”

“Members of the environmentally important order Planctomycetales are ubiquitously distributed in both terrestrial habitats and in fresh- and saltwater environments and may be correlated with slight eutrophication (18, 19, 29, 36, 50, 52).”

“could be explained by an accumulation of certain organic compounds on the membranes from the feed waters over time which could promote their growth since this group is known to metabolize phytoplankton degradation products (Fuerst 1995 ; Morris et al.”

“Consistent with their independent phylogenetic position, members of the Planctomycetes show several characteristics that are unusual for Bacteria (Fuerst 1995), such as the lack of peptidoglycan as a component of their cell wall (Konig et al. 1984; Liesack et al. 1986), a budding reproduction, and…”

“The 16S rRNA genes of both groups share signature positions that are not present in other bacteria (Fuerst, 1995) and, finally, the ribosomal spc operon in all chlamydiae sequenced to date, as well as in ‘Rhodopirellula baltica’ SH 1, is devoid of the ribosomal protein L30, as in some other bacteria, e.”

“…on 16S rRNA analysis, one implying that the planctomycetes represent an ancient group of bacteria descending from a group branching close after that the eubacteria diverged from the progenote, and the other suggesting that they represent a very rapidly evolving group of bacteria (Fuerst 1995).”

“The nucleoid, typically condensed in Planctomycetales (Fuerst, 1995), is shown in Figs 6(a) and 7(c), and multiple nucleoids, possibly from a single folded nucleoid being sectioned more than once, can be seen in Fig.”

“It is considered one of the most unusual and mysterious groups of prokaryotic microorganisms [1, 2].”

“…coat-like proteins (Santarella-Mellwig et al. 2010), sterol synthesis (Pearson et al. 2003), outer-membrane crateriform structures (Boedeker et al. 2017; Fuerst 1995; Schmidt and Starr 1979) and FtsZ-independent budding reproduction (Bernander and Ettema 2010; Fuerst 1995; Jogler et al. 2012).”

“In addition to the Proteobacteria, some members of the phylum Planctomyces appear to have membranous flagellar sheaths, including Pirella marina and several members of the genus Planctomycetes [4,5].”

“kingdom-level division on the basis of 16S rRNA analyses [1-6].”

“The greater abundance of Planctomycetes observed at EI and PB sites, situated north-east of LI, might reflect a productivity gradient because algae or their decomposition products have been reported to enrich Planctomycetes populations (Fuerst, 1995), Planctomycetes have been previously associated with surface chlorop…”

“and acidic environments (Fuerst 1995; Neef et al. 1998; Wang et al. 2002; Kulichevskaia et al. 2006; Schlesner 1994; Lage and Bondoso 2012), as part of the microbial wall community usually found in caves from various parts of the world (Borsodi et al.”

“Planctomycetes are characterized by a wide distribution in most marine environments (Fuerst 1995; Polymenakou et al. 2009) and they catalyze important transformations in global carbon and nitrogen cycles (Glöckner et al. 2003).”

“Planctomycetes are a phylum of budding bacteria with a peptidoglycan-free proteinaceous cell wall of increasing interest for ecology, genomics and, particularly, cell biology and microbial evolution (Fuerst 1995).”

“Chemoorganotrophs capable of hydrolyzing biopolymers, of fermenting or respiring organic compounds with NO3 - or other electron acceptors are well represented in Planctomycetes (Fuerst 1995; Schlesner et al. 2004), Pseudomonadales, Oceanospirillales, b-Proteobacteria (excl.”

“…relative abundance of known denitrifiers taxa such as the members of Comamonadaceae and Peptococcaceae family, Pirellula sp., and Acholeplasma sp. (Fuerst 1995; Chung, Shin and Oh 2009; Ezaki et al. 2009; Willems 2014) was higher in lakes Cotacotani and Piacota during the wet season, when nitrate…”

“They display a number of unusual phenotypic features, including peptidoglycan‐less cell walls, short 5S rRNA and an unlinked rrn operon organization (41).”

“Cultured members of the Planctomycea, abundant in our libraries, include aerobic or facultative anaerobic chemoheterotrophs, some capable of nitrate reduction (Fuerst, 1995).”

“Members of the division Planctomycetes have also been shown to contain eukaryote-like features including membrane-bounded nucleoids [17,18] cell walls lacking in peptidoglycan [19] and fatty acids containing palmitic and stearic acid in addition to other features that are more typical of microbial eukaryotes [20].”

“For example, Planctomycetes, which contains several aquatic microbes (Fuerst, 1995), was frequently found when the backward trajectories followed oceanic routes (Figures 3A, 5).”

“The cell surface in most archaeal species possesses a proteinous S-layer, as in bacteria, but these species do not possess PG, except that PG-like polymers have been detected in some of the Euryarchaeota (Albers and Meyer, 2011).”

“This group of bacteria influence the carbon exchange process between the geosphere and the atmosphere and thus the global climate by converting organic material, such as “marine snow”, into carbon dioxide [2, 3].”

“2003), and the Planctomycetes group also includes chemoorganotrophs, autotrophs, and phototrophs (Fuerst 1995; Miskin et al. 1999).”

“Initially described in the early twentieth century (Gimesi 1924), the phylum remained poorly understood for decades, with only a handful of species successfully isolated, cultivated and characterized (Fuerst 1995; Schlesner 1986, 1989; Schlesner and Stackebrandt 1986).”

“In comparison, k-selected microbiota, or slow-growing microflora, with relatively stable biological populations usually aggregate in BS (Fuerst 1995; Fierer et al.”

“Most Planctomycetes members can form small flagellated swarmer cells, which swim before attaching and reproducing, when they begin aerobic decomposition of the macromolecule substrate (Fuerst 1995).”

“Gemmata -like bacteria have been isolated from a range of habitats ranging from freshwater, soil, acid bogs and wastewater plants indicating that they are a metabolically diverse group of which very little is currently known ( Fuerst 1995 ; Chouari et al.”

“2010), and crateriform structures of the outer membrane (Boedeker et al. 2017; Fuerst 1995).”

“Keywords: anammox bacteria, Kuenenia stuttgartiensis, S-layer, glycoprotein, O-glycan, methylation INTRODUCTION From early on in the study of Planctomycetes, their cell biology has been a topic that has sparked much interest (Fuerst and Webb, 1991; Fuerst, 1995; Lindsay et al., 1997, 2001).”

“Planctomycetes is a bacterial phylum displaying exceptional physiological and morphological features (Fuerst 1995; Lage et al. 2019; Staley et al. 1992; Ward 2010; Wiegand et al. 2020).”

“Also, Isosphaeraceae (Planctomycetales order) and Paenibacillus (Paenibacillaceae family) are also key taxa in module 2 and closely associated with nutrient cycling and plant growth promoting (77, 78).”

“The M3 and M4 secondary reservoirs respectively displayed important abundances of Planctomycetes and Verrucomicrobiae which have been found in soil, freshwater (Australian dam, Hungarian pond) and seawater (the Californian Current) ( Fuerst, 1995; Freitas et al., 2012).”

“The planctomycetes are a phylum of bacteria that have a unique cell compartmentalization, yeast-like budding cell division and peptidoglycan-less proteinaceous cell walls [1].”

“Pirelulla and Planctomyces species belonging to Planctomycetes were often associated with algae bloom [25,26].”

“1), as previously reported for 2D imaging (10, 11, 13).”

“The ecology, phylogeny, and cell biology of the planctomycetes have been recently reviewed (11).”

“Crateriform structures, a defining feature within the Planctomycetes phylum [1], were visible over the entire surface of negatively stained MBLW1 T cells.”

“It is now known that these bacteria are ubiquitous and display several specificities in terms of cell structure (e.g. cell compartmentalization), genetics and physiology (Fuerst, 1995; Lindsay et al., 2001).”

“Planctomycetes are characterized by a wide distribution in most marine environments (Fuerst, 1995; Polymenakou et al., 2009) and catalyze important transformations in the global carbon and nitrogen cycles (Glöckner et al., 1999).”

“They are found in aquatic and soil environments (3),”

“Isolate IP1 is a slow growing bacterium as typically exhibited by planctomycetes (Fuerst 1995).”

“Their ultrastructure is consistent with them being planctomycetes (Fuerst 1995), possessing R J.”

“Members of the Chlamydiae do not encode FtsZ and originally were thought to completely lack PG (Tamura and Manire, 1967; Garrett et al., 1974; Barbour et al., 1982; Fox et al., 1990).”

“…with unusual cell morphology and organization, a complex life cycle, unique membrane composition, specific mechanisms for transport of high-molecular substrates into the cell, and other features (Staley et al., 1992; Fuerst, 1995; Boedeker et al., 2017; Reintjes et al., 2017; Wiegand et al., 2018).”

“Phylum Planctomycetes is represented by a broad distribution in most of the marine sediments (Fuerst 1995; Polymenakou et al.”

“They display a number of unusual phenotypic features for bacteria, including peptidoglycan-less cell walls, short 5S rRNA and an unlinked rrn operon organization (Fuerst, 1995).”

“The phylum Planctomycetes is a remarkable Gram-negative staining group of bacteria, having the characteristics of a compartment, bud production and lack peptidoglycan (Konig et al., 1984; Fuerst, 1995), they are widely distributed in marine habitats and play critical roles in biogenic elements cycling in the ocean.”

“Pirellula-like and Gemmataceae are chemoorganotrophic and ubiquitous aquatic bacteria are often detected in anoxic or micro-oxic habitats despite taxonomy describing representatives of these bacteria as strictly aerobic (Fuerst, 1995; Kulichevskaya et al., 2020).”

“2006), macroalgae (Lage 51 and Bondoso 2011) and plants (Fuerst 1995; Derakshani et al. 2001; Kulichevskaia et al. 2006).”

“The Planctomycetota (formerly, Planctomycetes) is one of the morphologically distinct, widespread, and most puzzling phyla of the domain Bacteria (Fuerst 1995; Jenkins and Staley 2013; Wiegand et al. 2018; Rivas-Marín and Devos 2018; Wiegand et al. 2020).”