The Paradigms They Are a-Changin’: past, present and future of PVC bacteria research

Abstract

These are exciting times for PVC researchers! The PVC superphylum is composed of the bacterial phyla Planctomycetes, Verrucomicrobia, Chlamydiae (those three founders giving it its name), Lentisphaerae and Kirimatiellaeota as well as some uncultured candidate phyla, such as the Candidatus Omnitrophica (previously known as OP3). Despite early debates, most of the disagreements that surround this group of bacteria have been recently resolved. In this article, we review the history of the study of PVC bacteria, with a particular focus on the misinterpretations that emerged early in the field and their resolution. We begin with a historical perspective that describes the relevant facts of PVC research from the early times when they were not yet termed PVC. Those were controversial times and we refer to them as the “discovery age” of the field. We continue by describing new discoveries due to novel techniques and data that combined with the reinterpretations of old ones have contributed to solve most of the discordances and we refer to these times as the “illumination age” of PVC research. We follow by arguing that we are just entering the “golden age” of PVC research and that the future of this growing community is looking bright. We finish by suggesting a few of the directions that PVC researches might take in the future.

Commentary: Manifold Routes to a Nucleus

“…However, their claim that bacteria from the Planctomycetes phylum display “nucleus-like compartmentation” is based on an outdated interpretation of the planctomycetal cell plan (Fuerst and Sagulenko, 2011). Various comprehensive reviews on the paradigm shift in the field of planctomycetal research were recently published (Devos, 2014a,b; Rivas-Marin and Devos, 2018; Wiegand et al, 2018) and are summarized in Figure 1.…”

“…Regarding the main aspect of their article “Manifold Routes to a Nucleus,” Hendrickson and Poole unfortunately do not mention most of the above discussed articles (Speth et al, 2012; Devos, 2014a,b; Rivas-Marin and Devos, 2018; Wiegand et al, 2018). By acknowledging that “the exact nature of this compartmentation is a matter of ongoing debate” they neglect the fact that the described findings do not question the nature of the compartments but their very existence.…”

Thalassoglobus polymorphus sp. nov., a novel Planctomycete isolated close to a public beach of Mallorca Island

“…It is now well accepted that Planctomycetes is a peculiar phylum of bacteria featuring a diderm bacterial cell envelope architecture. Some strains have been shown to have expanded cytoplasmic membranes, a different composition of peptidoglycan or condensed DNA, but all of these characteristics are variations rather than exceptions to the Gram-negative cell plan (Devos 2014a, b;Boedeker et al 2017;Rivas-Marín and Devos 2018).…”

Lignipirellula cremea gen. nov., sp. nov., a planctomycete isolated from wood particles in a brackish river estuary

“…Planctomycetes is a phylum of bacteria which were once thought to have several exceptional eukaryotelike traits Devos and Reynaud 2010;Fuerst and Sagulenko 2011;Fuerst and Webb 1991;König et al 1984;Lindsay et al 1997;Lonhienne et al 2010). These have since been re-examined and re-interpreted (Acehan et al 2013;Boedeker et al 2017;Jeske et al 2015;Jogler 2014;Jogler et al 2011;Jogler and Jogler 2013;Neumann et al 2014;Rast et al 2017;Rivas-Marin et al 2016b;Rivas-Marín and Devos 2018;Santarella-Mellwig et al 2013;van Teeseling et al 2015). The cell envelope architecture of Planctomycetes was shown to resemble that of Gram-negative bacteria Devos 2014).…”